All categories

2 years ago

Alegbra 2: pls help!!

Mathematics

1 answer:

siniylev [52]2 years ago

8 0

Answer:

Sean's rocket lands 3 seconds after Kiara's rocket.

Step-by-step explanation:

Kiara: f(t)= -16t² + 80t

Sean: h(t) = -16t² + 120t + 64

Assume that both rockets launch at the same time. We need to be suspicious of Sean's rocket launch. His equation for height has "+64" at the end, whereas Kiara's has no such term. The +64 is the starting height iof Sean's rocket. So Kiara has a 64 foot disadvantage from the start. But if it is a race to the ground, then the 64 feet may be a disadvantage. [Turn the rocket upside down, in that case. :) ]

We want the time, t, at which f(t) and h(t) are both equal to 0 (ground). So we can set both equation to 0 and calculate t:

Kiara: f(t)= -16t² + 80t

0 = -16t² + 80t

Use the quadratic equation or solve by factoring. I'll factor:

0 = -16t(t - 5)

T can either be 0 or 5

We'll choose 5. Kiara's rocket lands in 5 seconds.

Sean: h(t) = -16t² + 120t + 64

0= -16t² + 120t + 64

We can also factor this equation (or solve with the quadratic equation):

0 = -8(t-8)(2t+1)

T can be 8 or -(1/2) seconds. We'll use 8 seconds. Sean's rocket lands in 8 seconds.

Sean's rocket lands 3 seconds after Kiara's rocket.

You might be interested in

M5_A3. The expected project completion time for the construction of a pressure vessel is 18 monthsand the project variance is 7.

snow_tiger [21]

Answer:

a) 0.3520

b) 0.9884

c) 0.1292

d) 0.1292

e) 0.7648

Step-by-step explanation:

Problems of normally distributed samples can be solved using the z-score formula.

In a set with mean $\mu$ and standard deviation $\sigma$ , the zscore of a measure X is given by

$Z = \frac{X - \mu}{\sigma}$

After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X.

In this problem, we have that:

The expected project completion time for the construction of a pressure vessel is 18 months. So $\mu = 18$ .

And the project variance is 7. The standard deviation is the square root of the variance, so $\sigma = \sqrt{7}$ .

a) What is the probability that the project will require at least 19 months?

The pvalue of the zscore of $X = 19$ is the probability that the project will require less than 19 months. So the probability that the project will require at least 19 months is the subtraction of 1 by this pvalue.

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{19 - 18}{\sqrt{7}}$

$Z = 0.38$

The pvalue of Z = 0.38 is 0.6480.

So the probability that the project will require at least 19 months is 1 - 0.6480 = 0.3520.

b) What is the probability that the project will be completed within 24 months?

This is the pvalue of the zscore of X = 24.

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{24 - 18}{\sqrt{7}}$

$Z = 2.27$

The pvalue of Z = 2.27 is .9884. This means that the probability that the project will be completed within 24 months is .9884.

c) What is the probability that the project will require at least 21 months?

Same logic as a). We find the pvalue of the zscore of X = 21, then we subtract 1 by this value.

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{21 - 18}{\sqrt{7}}$

$Z = 1.13$

The pvalue of Z = 1.13 is 0.8708.

So the probability that the project will require at least 21 months is 1 - 0.8708 = 0.1292.

d) What is the probability that the project will be completed within 15 months?

Same logic as b). This is the pvalue of the zscore of X = 15.

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{15 - 18}{\sqrt{7}}$

$Z = -1.13$

The pvalue of Z = -1.13 is .1292. This means that the probability that the project will be completed within 15 months is .1292.

e) What is the probability that the project will take between 16 and 24 months to complete?

This is the pvalue of Z = 24 subtract by the pvalue of Z = 16.

In b), we found that the pvalue of Z = 24 is .9884

Now we find the pvalue of Z = 16

$Z = \frac{X - \mu}{\sigma}$

$Z = \frac{16 - 18}{\sqrt{7}}$

$Z = -0.76$

The pvalue of Z = -0.76 is 0.2236

So the probability that the project will take between 16 and 24 months to complete is 0.9884 - 0.2236 = 0.7648

8 0

4 years ago

Help ASAP please! I dont understand.

igomit [66]

All of the box numbers are decide by the bottom numbers. Ex: 3+4=7, the top box is seven above 3 and 4. So you would add 16 and 17 which is 33. The answer is 33.

7 0

3 years ago

Read 2 more answers

Please hellppp asappp

Firlakuza [10]

Answer:

Step-by-step explanation:

The II and III quadrant are all negative x values, and the I and II quadrants are all positive y values!

4 0

3 years ago

Read 2 more answers

I need 7-10 pictured