Answer:
Step-by-step explanation:
x + 6y = 9
-x + 2y = -15
-------------------add
8y = - 6 <=== u see that the x terms cancel each other out
Answer:

Step-by-step explanation:
given,
y=5√sinx
Volume of the solid by revolving

a and b are the limits of the integrals
now,



![V =25\pi [-cos x]_{\pi/4}^{\pi/2}](https://tex.z-dn.net/?f=V%20%3D25%5Cpi%20%5B-cos%20x%5D_%7B%5Cpi%2F4%7D%5E%7B%5Cpi%2F2%7D)
![V =25\pi [-cos (\pi/2)+cos(\pi/4)]](https://tex.z-dn.net/?f=V%20%3D25%5Cpi%20%5B-cos%20%28%5Cpi%2F2%29%2Bcos%28%5Cpi%2F4%29%5D)
![V =25\pi [0+\dfrac{1}{\sqrt{2}}]](https://tex.z-dn.net/?f=V%20%3D25%5Cpi%20%5B0%2B%5Cdfrac%7B1%7D%7B%5Csqrt%7B2%7D%7D%5D)

volume of the solid generated is equal to 
Answer:
$35.00
Step-by-step explanation:
I just did it rn
To solve this problem we will start by calculating time needed for each of them to fill the pool.
We have formula:
Volume = rate * time
Or
time = volume / rate
Wilma:
time = 9900 / 900
time = 11h
Betty:
time = 9900 / 500
time = 19.8h
Now we substract these two numbers:
time_difference = 19.8 - 11 = 8.8h
Betty needs 8.8 hours more than Wilma to fill the pool.
The answer is 30 because 1/8 of 40 is 5 so 40-5 = 35 and 1/7 of 35 is 5 so 35-5 = 30