Answer:
![81\pi](https://tex.z-dn.net/?f=81%5Cpi)
Step-by-step explanation:
Area = pi*r^2
Area = pi*9^2
Area = ![81\pi](https://tex.z-dn.net/?f=81%5Cpi)
To find the average, you have to add all the numbers up and then divide by the amount of numbers you added together.
Equation: (86+87+91+x)/4=98
Solve for x:
86+87+91+x=98*4
264+x=392
x=392-264
x=128
The fourth number is 128
Answer:
The answer is 23.
Step-by-step explanation:
Our equation here is (2x + y) + 5.
If x=4, and y=10, let's plug that in into our variables, and simplify!
[2(4) + (10)] + 5
= [8+10] + 5
=[18] +5
=23