Orla says that x = 5 is a solution of x² + 3x - 10 = 0 and Fiona says that x = -5 is
a solution of x² + 3x -10=0.

One of the answers is correct. Say which answer is correct and justify your answer

Answers

Answer 1

Answer:

Fiona is correct

Step-by-step explanation:

Substitute x = 5 and x = - 5 into the left side of the equation and if equal to the right side then it is a solution of the equation.

x = 5 : 5² + 3(5) - 10 = 25 + 15 - 10 = 30 ≠ 0 ← not a solution

x = - 5 : ( - 5)² + 3(- 5) - 10 = 25 - 15 - 10 = 0 ← correct

Then Fiona is correct with x = - 5 being the solution


Related Questions

Please help me with this real quick

Answers

Answer: 7.5 miles

Step-by-step explanation:

think of it as a triangle; the bold line is the hypotenuse, or x.

 8   |\   x

      |_\              it's not a good triangle but you get the point

       6

and then get out pythagorean theorem: a^2+b^2=c^2

put the numbers in: 8^2 + 6^2 = x^2

do some math:

64+36=x^2

100=x^2 (and then find square root)

10=x

BUT, it said each unit was 3/4 of a mile, so we must multiply 10 by 3/4 to get the actual distance, which is 7.5

An aquarium owns 5 identical tanks. All together, the tanks can hold 86 gallons of water. How much water can each tank hold?
All tanks together =

Answers

Answer:  17.2 for each tank

Ms. Clark is building a patio that is 4 yards long and 3 yards wide. She has enough bricks to cover an area of 14 square yards. Does Ms. Clark have enough bricks to build the patio? Explain.​

Answers

Answer:

DONT CLICK THE LINK!!!! IT IS A BOT. THEY WILL. HACK.

Step-by-step explanation:

Given, we know that she has 14 bricks.

We also know that the patio is 4 yards long and 3 yards wide. If we multiply those two numbers together we get 12.

So, if we do the math 14-12=2 bricks left over.

Therefore, she will have enough bricks to build the patio.

Help me please ( on the image )

Answers

Answer:

[tex]\frac{\pi}{3}[/tex] radians

Step-by-step explanation:

Number of hours on a clock = 12

Since, measure of a circle at the center = 360°

Measure of central angle formed by the arc between each number (representing hours) = [tex]\frac{360}{12}[/tex]

                                  = 30°

Central angle formed by the arc intercepted by the hands of the clock at 8:00 = 4 × 30°

        = 120°

Therefore, angle measure in radians = [tex]\frac{\pi }{360}\times (120^0)[/tex]

                                                              = [tex]\frac{\pi }{3}[/tex]

Angle formed by the hands of the clock at 8:00 = [tex]\frac{\pi}{3}[/tex] radians

The waiting time W for accessing one record from a computer database is a random variable uniformly distributed between 0 and 28 milliseconds. The read time R for moving the information from the disk to the main memory is 7 milliseconds. The random variable X milliseconds is the total access time (waiting time + read time) to get one block of information from the disk. Before performing a certain task, the computer must access 6 different blocks of information from the disk. (Access times for different blocks are independent of one another.). Compute the followings:

a. E[X]
b. Vae[X]
c. E[A]

Answers

Solution :

Let

Waiting time for accessing one record = W

Read time for moving the information = R

Total time for accessing to get one block of information = X

So, the random variable X is defined as :

X = W + R

  = W + 7

a). Calculating E(X)

E(X) = E(W+7)

      = E(W) + 7

      [tex]$=\int_{0}^{28}\frac{1}{28-0}w dw +7$[/tex]

       [tex]$=\frac{1}{28}\int_{0}^{28}w dw +7$[/tex]

       [tex]$=\frac{1}{28}\left[\frac{w^2}{2}\right]_0^{28}+7$[/tex]

      [tex]$=\frac{1}{56}\left[28^2\right]+7$[/tex]

      [tex]$=\frac{28}{2}+7$[/tex]

     = 14 + 7

     = 21

b). Calculating Var(X)

V(X) = V(W+7)

      = V(W)+0

      = V(W)

     = [tex]$E(W^2)-[E(W)]^2$[/tex]

     [tex]$=\int_0^{28}\frac{1}{28}w^2 dw-[14]^2$[/tex]

    [tex]$=\frac{1}{28}\left[\frac{w^3}{3}\right]_0^{28}-196$[/tex]

   [tex]$=\frac{1}{28\times 3}\times 28^3-196$[/tex]

  [tex]$=\frac{28\times 28}{3}-196$[/tex]

 = 65.33

c). Considering A is the random variable that can be defined as follows:

A = 6(W+7)

   =6W + 42

So calculating E(A)

E(A) = E(6W + 42)

      = E(6W) +42

      = 6E(W) + 42

     = 6(14) + 42

     = 84 + 42

     = 126

Which choice is the slope-intercept equation of the line shown below?
(1,2)

(0, -1)

A. y = 3x - 1
B. y = 2x-1
C. y = 2x + 1
D. y = 3x

Answers

Answer:

C is my answer

Step-by-step explanation:

You need a 70% alcohol solution. On hand, you have a 40 mL of a 35% alcohol mixture. You also have 75% alcohol mixture. How much of the 75% mixture will you need to add to obtain the desired solution?

Answers

Answer:

250 ml of the 75% mixture are needed to obtain the desired solution.

Step-by-step explanation:

Since I need a 70% alcohol solution, and on hand, I have a 40 mL of a 35% alcohol mixture, and I also have 75% alcohol mixture, to determine how much of the 75% mixture will you need to add to obtain the desired solution, the following calculation must be performed:

100 x 0.75 + 0 x 0.35 = 75

90 x 0.75 + 10 x 0.35 = 71

89 x 0.75 + 11 x 0.35 = 70.6

87.5 x 0.75 + 12.5 x 0.35 = 70

12.5 = 40

87.5 = X

87.5 x 40 / 12.5 = X

3,500 / 12.5 = X

280 = X

Therefore, 250 ml of the 75% mixture are needed to obtain the desired solution.

app 19.study
Tools
Tools
Probability
Jacob performed an experiment with a weighted die, numbered 1 to 6. He rolled the die 125 times and recorded the results.
Complete the table below.
0.232
37
24
0.176
18
0.048
0.104
22
Result of Roll
Frequency
Experimental
Probability
1
2
13
3
0.144
4
29
5
0.296
6
Reset
Submit

Answers

Answer:

[tex]1 \to 22 \to 0.176[/tex]

[tex]2 \to 13 \to 0.104[/tex]

[tex]3 \to 18 \to 0.144[/tex]

[tex]4 \to 29 \to 0.232[/tex]

[tex]5 \to 37 \to 0.296[/tex]

[tex]6 \to 6 \to 0.048[/tex]

Step-by-step explanation:

Given

[tex]n = 125[/tex]

See attachment for proper table

Required

Complete the table

Experimental probability is calculated as:

[tex]Pr = \frac{Frequency}{n}[/tex]

We use the above formula when the frequency is known.

For result of roll 2, 4 and 6

The frequencies are 13, 29 and 6, respectively

So, we have:

[tex]Pr(2) = \frac{13}{125} = 0.104[/tex]

[tex]Pr(4) = \frac{29}{125} = 0.232[/tex]

[tex]Pr(6) = \frac{6}{125} = 0.048[/tex]

When the frequency is to be calculated, we use:

[tex]Pr = \frac{Frequency}{n}[/tex]

[tex]Frequency = n * Pr[/tex]

For result of roll 3 and 5

The probabilities are 0.144 and 0.296, respectively

So, we have:

[tex]Frequency(3) = 125 * 0.144 = 18[/tex]

[tex]Frequency(5) = 125 * 0.296 = 37[/tex]

For roll of 1 where the frequency and the probability are not known, we use:

[tex]Total \ Frequency = 125[/tex]

So:

Frequency(1) added to others must equal 125

This gives:

[tex]Frequency(1) + 13 + 18 + 29 + 37 + 6 = 125[/tex]

[tex]Frequency(1) + 103 = 125[/tex]

Collect like terms

[tex]Frequency(1) =- 103 + 125[/tex]

[tex]Frequency(1) =22[/tex]

The probability is then calculated as:

[tex]Pr(1) = \frac{22}{125}[/tex]

[tex]Pr(1) = 0.176[/tex]

So, the complete table is:

[tex]1 \to 22 \to 0.176[/tex]

[tex]2 \to 13 \to 0.104[/tex]

[tex]3 \to 18 \to 0.144[/tex]

[tex]4 \to 29 \to 0.232[/tex]

[tex]5 \to 37 \to 0.296[/tex]

[tex]6 \to 6 \to 0.048[/tex]

Explain how you found your answer

Answers

Answer:

29°

Step-by-step explanation:

151° + a=180°

We know the sum of angles in a straight line is 180°

a= 180°-151°

The sign changed as it changed sides

a= 29°

The number of hours per week that the TV is turned on is determined for each family in a sample.
The mean of the data is 37 hours.
The median is 33.2 hours.
Twenty four of the families in the sample watched TV for less than 22 hrs per week.
The 16th percentile is 22hrs.
150 families participated in the study.
The first percentile is greater than or equal to 22 hours: True or False?

Answers

Answer:

False, the first percentile is less than 22 hours.

Step-by-step explanation:

xth percentile:

If a measure is said to be in the xth percentile, it means that x% of the measures are smaller than it, and (100-x)% are larger.

Twenty four of the families in the sample watched TV for less than 22 hrs per week. In the sample, there are 150 families.

This means that 22 is the:

24*100%/150 = 16th percentile.

The first percentile is greater than or equal to 22 hours: True or False?

The first percentile is less than the 16th percentile, which is 22. This means that this is false, the first percentile is less than 22 hours.

Find the median of the dot plot below 5 6 7 8 9 10 11 12 13​

Answers

Answer:

The median is 9

Step-by-step explanation:

Answer:

Hey love! Answer: 9

Step-by-step explanation:

these are the numbers 5 6 7 8 (9) 10 11 12 13

the median is simply just the one in the middle so this one is 9 because it has 4 numbers in front and 4 numbers after

Hope this helps!

What is the answer to this problem?

Answers

Answer:

Surface area = 24in

Step-by-step explanation:

I think its 6in x 4in

so like since the green cylinder is 6in i think you multiply it with the purple (sorry if I’m wrong)

PLEASE HELP PLEASE (dont do links)

Answers

Answer:

B

-2(0)²+24(0)-54

= -54

Answer:

I think its C

Step-by-step explanation:

y intercepts (0,-54)

For which value of k does Limit as x approaches kf(x) = 4?

0
2
6
8

Answers

Answer:

2

Step-by-step explanation:

on Edge

Answer: 2

Step-by-step explanation:

have a great day!

which equation is equivalent to xy (3x + 2y) = 4

Answers

Answer:

the value x is 0 and the value of y is 2

What is the answer to this

Answers

Answer:

5 f

Re-order terms so that constants are on the left

. 5

5 f

solution

5 f

You have been given the task of designing a study concerning the lifetimes of five different types of electric motor. The initial question to be addressed is whether there are differences in mean lifetime among the five types. There are 20 motors, four of each type, available for testing. A maximum of five motors can be tested in a day. The ambient temperature differs from day to day, and this can affect motor lifetime.
a. Describe how you would choose the five motors to test each day. Would you use a completely randomized design? Would you use any randomization at all?
b. If X;j represents the measured lifetime of a motor of type i tested on day j, express the test statistic for testing the null hypothesis of equal lifetimes in terms of the Xir

Answers

Answer:

a-As the only factor of interest is type of electric motor, thus instead of using 1-factor randomization, a randomized block design is used where at maximum one motor of each type is tested every day.

b- The test statistic is given as

[tex]F_{I-1,(I-1)(J-1)}=\dfrac{12\left(\Sigma^{5}_{i=1}\bar{X}^{2}_{i.}-IJ\bar{X}^2_{..}\right) }{\Sigma^5_{i=1}\Sigma^4_{j=1}\left(X_{ij}-\bar{X}_{i.}-\bar{X}_{.j}+\bar{X}_{..}\right)^2}[/tex]

Step-by-step explanation:

a-

This is done such that the days are considered as blocks and the randomization is only occuring within the block. The order of testing is random. However the condition is implemented such that one motor of each type is tested each day.

b-

The F-Value is given as

[tex]F-Value=\dfrac{MSA}{MSAB}[/tex]

Here MSA is given as

[tex]MSA=\dfrac{J\Sigma^I_{i=1}(\bar{X}_{i.}-\bar{X}_{..})^2}{I-1}[/tex]

Here

I is the number of types which is 5J is the number of motors of each type which is 4[tex]\bar{X}_{i.}[/tex] is the row-wise mean which is given as [tex]\bar{X}_{i.}=\dfrac{1}{J}\Sigma^J_{j=1}X_{ij}[/tex][tex]\bar{X}_{..}[/tex] is the sample grand mean which is given as [tex]\bar{X}_{..}=\dfrac{1}{IJ}\Sigma^I_{i=1}\Sigma^J_{j=1}X_{ij}[/tex]

Similarly MSAB is given as

[tex]MSAB=\dfrac{\Sigma^I_{i=1}\Sigma^J_{j=1}\left(X_{ij}-\bar{X}_{i.}-\bar{X}_{.j}+\bar{X}_{..}\right)^2}{(I-1)(J-1)}[/tex]

Here

I is the number of types which is 5J is the number of motors of each type which is 4[tex]\bar{X}_{i.}[/tex] is the row-wise mean which is given as [tex]\bar{X}_{i.}=\dfrac{1}{J}\Sigma^J_{j=1}X_{ij}[/tex][tex]\bar{X}_{..}[/tex] is the sample grand mean which is given as [tex]\bar{X}_{..}=\dfrac{1}{IJ}\Sigma^I_{i=1}\Sigma^J_{j=1}X_{ij}[/tex][tex]\bar{X}_{.j}[/tex] is the column-wise mean which is given as [tex]\bar{X}_{.j}=\dfrac{1}{I}\Sigma^I_{i=1}X_{ij}[/tex][tex]X_{ij}[/tex] is the any motor j of type i

By putting these values and simplifying, equation becomes:

[tex]F-Value=\dfrac{MSA}{MSAB}\\\\F-Value=\dfrac{\dfrac{J\Sigma^I_{i=1}(\bar{X}_{i.}-\bar{X}_{..})^2}{I-1}}{\dfrac{\Sigma^I_{i=1}\Sigma^J_{j=1}\left(X_{ij}-\bar{X}_{i.}-\bar{X}_{.j}+\bar{X}_{..}\right)^2}{(I-1)(J-1)}}\\\\F-Value=\dfrac{\dfrac{4\Sigma^5_{i=1}(\bar{X}_{i.}-\bar{X}_{..})^2}{5-1}}{\dfrac{\Sigma^5_{i=1}\Sigma^4_{j=1}\left(X_{ij}-\bar{X}_{i.}-\bar{X}_{.j}+\bar{X}_{..}\right)^2}{(5-1)(4-1)}}\\\\[/tex]

This is further simplified as

[tex]F-Value=\dfrac{\dfrac{4\Sigma^5_{i=1}(\bar{X}_{i.}-\bar{X}_{..})^2}{4}}{\dfrac{\Sigma^5_{i=1}\Sigma^4_{j=1}\left(X_{ij}-\bar{X}_{i.}-\bar{X}_{.j}+\bar{X}_{..}\right)^2}{12}}\\\\F-Value=\dfrac{\Sigma^5_{i=1}(\bar{X}_{i.}-\bar{X}_{..})^2}{\dfrac{\Sigma^5_{i=1}\Sigma^4_{j=1}\left(X_{ij}-\bar{X}_{i.}-\bar{X}_{.j}+\bar{X}_{..}\right)^2}{12}}\\\\[/tex]

The numerator can be written as

[tex]F-Value=\dfrac{\Sigma^{5}_{i=1}\bar{X}^{2}_{i.}-IJ\bar{X}^2_{..}}{\dfrac{\Sigma^5_{i=1}\Sigma^4_{j=1}\left(X_{ij}-\bar{X}_{i.}-\bar{X}_{.j}+\bar{X}_{..}\right)^2}{12}}\\\\F-Value=\dfrac{12(\Sigma^{5}_{i=1}\bar{X}^{2}_{i.}-IJ\bar{X}^2_{..})}{{\Sigma^5_{i=1}\Sigma^4_{j=1}\left(X_{ij}-\bar{X}_{i.}-\bar{X}_{.j}+\bar{X}_{..}\right)^2}}\\[/tex]

What is the surface area of the right prism below? A 432 sq units B. 448 sq units C. 480 sq units D. 400 sq units​

Answers

[tex]\huge{\textbf{\textsf{{\color{pink}{An}}{\red{sw}}{\orange{er}} {\color{yellow}{:}}}}}[/tex]

D. 400 sq units

ThanksHope it helps

The surface area of the right prism given below is 432 square units.

What is Surface Area?

The area of a three dimensional object on it's outer surface is called the surface area of the object.

Given a right prism.

The right prism consists of three rectangular faces and two triangular faces.

Area of a triangular face = 1/2 × 8 × 6 = 24

Area of two triangular faces = 2 × 24 = 48 square units

Area of rectangular faces = (10 × 16) + (8 × 16) + (6 × 16)

                                          = 384 square units

Total area of the prism = 48 square units + 384 square units

                                      = 432 square units

Hence the total area of the prism is 432 square units.

Learn more about Surface Area here :

https://brainly.com/question/29298005

#SPJ7

As reported in Trends in Television, the proportion of US households who have at least one VCR is 0.592. If 8 households are selected at random, without replacement, from all US households, what is the (approximate) probability that the number having at least one VCR is exactly 4. Be sure to use many decimal places in your calculations (at least 4), but report your answer to three decimal places.

Answers

Answer:

0.23825

Step-by-step explanation:

Given :

p = 0.592 ; number of trials, n = 8

x = 4 ; q = 1 - p = 1 - 0.592 = 0.408

Using the binomial probability relation :

P(x = x) = nCx * p^x * q^(n-x)

P(x = 4) = 8C4 * 0.592^4 * 0.408^4

P(x = 4) = 70 * 0.592^4 * 0.408^4

P(x = 4) = 0.23825

1.A woman is flying a kite. If she has 80 feet of string out and the kite is 55 feet up in the air,
what is the kite's angle of inclination?

Answers

Answer:

25 feet

Step-by-step explanation:

Helppppppppppppppppppppp

Answers

D) No, because the y-intercepts are different

Mark with crown please!

Dan bought 20 bunches of seedless green grapes for $48. How many bunches can Kali buy if she has $12?

5

29

4

6​

Answers

Answer:

48/20=2.4

12/2.4=5

Step-by-step explanation:

Kai can buy 5 bunches of grapes if she has $12.

Answer:

It's 29.

Step-by-step explanation:

48/20=2.4

12x2.4=28.8

Round up to 29.

does the graph of this equation widen or narrow from the parent function? g(x)=3/4(x-5)^2+12

Answers

9514 1404 393

Answer:

  widen

Step-by-step explanation:

The vertical scale factor is 3/4, so the vertical extent is shortened at a given x-value distance from the axis of symmetry. That will give the appearance of making the parabola (slightly) wider.

Answer:

Widen is the answer.

Step-by-step explanation:

#CarryOnLearning

which equation represents a line that passes through (5,4) with a slope of 2/5

Answers

Answer:

y = 2/5x +2

Step-by-step explanation:

y - 4 = 2/5(x -5)

y-4 = 2/5x -2

y = 2/5x +2

The cost of a spa treatment is $42 and there is sales tax of 6%. What is the total cost of the spa treatment?

Answers

Answer:

$52.92 has been spent in total for spa treatment and this amount includes a sales tax of $2.52 and a tip of $8.40.

Step-by-step explanation:

Cost of the spa treatment = $42

Percentage of sales tax = 6%

Percentage of tips = 20%

Normally the tips amount is calculated before adding sales tax.

Then

Amount of tips given = (20/100) * 42

                                 = (1/5) * 42

                                 = 8.40 dollars

Amount of sales tax taken = (6/100) * 42

                                          = 252/100

                                          = 2.52 dollars

Then

The total amount spent for spa treatment = (42 + 8.40 + 2.52) dollars

                                                                  = 52.92 dollars

What is the slope of the line graphed below? (-1,3) (-2,-1)

Answers

Answer:

the slope of (-1,3) (-2,-1) is 4

jada uses a pitcher to fill a pot of water. the pitcher holds 8/10 liter of water. it takes 12 full pitchers of water to fill the pot. what is the total amount of water that the pot holds?

Answers

Answer:

The pot can hold 9 6/10 liters of water

Step-by-step explanation:

Since you know that the pitcher can hold 8/10 liters of water and that Jada has to fill the pitcher 12 times to fill the pot you would first convert the 8/10 liters that the pitcher can hold to a decimal so that would become 0.8 liters of water and then you would multiply the 0.8 by 12 to get 9.6 liters of water and then you can convert that back to a fraction which would be 9 6/10 liters of water. So the pot can hold 9 6/10 liters of water

I've been asking since yesterday :(

Candace is designing a rectangular garden. The garden's diagonal must be 37.7 feet, and the ratio between the garden's base and height must be 12:5. Find the length of the garden's base and height. The garden's base is feet and its height is​

Answers

Answer:

Step-by-step explanation:

let the base=12x

and height=5x

(12x)²+(5x)²=37.7²

144x²+25x²=37.7²

169x²=37.7²

(13x)²=37.7²

13x=37.7

x=37.7/13=2.9

base=12×2.9=34.8 ft

height=5×2.9=14.5 ft

Tori's Burgers cooks its burgers either well done or medium. Last night the restaurant served
25 burgers in all, 5 of which were well done. What percentage of the burgers were well done?
Write your answer using a percent sign (%).

Answers

Answer: 20%
5/25 = .2
.2 x 100 = 20%

At the beginning of the school year, Jamie had $500 in her savings account. She wants to have at least $200 left in the account at the end of the school year. Each week, she withdraws $30 for spending money. To determine how many weeks she can spend $30, Jamie wrote and solved this inequality.

500 − 30x ≥ 200
−500 −500
−30x ≥ −300
x ≥ 10
Review Jamie’s work. What was her error?

Answers

Her error was that she misplaced the numbers

-30x ≥ -300

its supose

to be -30x ≥ 200

Answer:

Jamie should have reversed the inequality when using the division property of inequality.

Step-by-step explanation:

Other Questions
A code consists of a single digit number from 0-9 and a letter from the alphabet. What is the probability that the code is 3Z? Write your answer as a fraction in simplest form. According to the Introduction to Exodus in the CEB Study Bible, scholars Group of answer choices can reconstruct the history of the Exodus with precision through archaeology prefer to speak about the biblical accounts of Exodus as cultural memory believe that the Exodus is entirely fictional have found supporting evidence for the evidence in the Dead Sea Scrolls Question refers to the image below.Cartoon illustration has the title, Health Coverage. It shows two beds, each with an occupant who appears stressed and sweating. In the first, the person is crushed by a pile of papers labeled, Multi-billion dollar paperwork costs. The footboard of the bed has a line graph labeled, U.S. Healthcare System, with a line that extends upward beyond the edges of the graph. In the second bed, the person is uncovered and shivering. The footboard of this bed has text that reads, Over 33 million Americans not insured.Library of Congress [LC-USZ62-126890]"Health coverage," by Herb Block, published in the Washington Post, May 3, 1991Why was health care reform a significant public debate in the 1990s? The majority of people who were unable to access medical care were illegal immigrants. Free trade agreements had led to a surge in demand for American health care. Most people agreed changes were needed, but they opposed raising taxes for it. Costs for medical care were rising, and fewer people had access to adequate care. Which of the following questions is the best example of a good research question?How did Howard Carter catalog and remove all of the artifacts from King Tuts tomb?How did King Tut most likely die?How was King Tuts tomb discovered, and what impact did it have on archaeology?When did King Tut become king, and what laws did he pass? Which is equivalent to 437O A 7B. 12OC 16OD. 64E. 81 Help due in 10 minutes helppp meee plssssss v^2 + 4v 1 = 0Solve using the quadratic formulawhat do I do? Alberto is painting a square canvas. What is the length of each side of the canvas?A = 121 in^2 please help me i need help because im failing help meh -.- fehfuihfewhuehwufguigfewi 35% of what number is 91?I need step by step too 2 3- = -x + 2 2x - 4 a cylinder shaped water pitcher has a radius of 5 inches and a height of 12.5 inches find the surface area of the pitcherA.5495 in B. 54.95 inC.549.5 in D. 5.495 in A. What is the current average beak depth in the Gizmo? A Motion Demonstration Model is shown in the diagram. At which of these positions does the ball have both the greatest potential energy and the least kinetic energy? A) Position W B) Position X C) Position Z D) Position Y Does this figure have symmetry? What happened to many Maldives islands due to rising sea levels? i need the answer pleaseee i cant figure out how to do this what is the chemical equation for aq nitrate ion reacts with s arsenic trihydride and produces s arsenic and g ammonia?