12^2+x^2=15^2
144+x^2=225
- 144 -144
=81= 9
X=9
We are trying to find miles/hour, which shows that we are going to be dividing the total number of miles by the total number of hours. Thus, in this case, the miles/hour rate will be:

He drove 40 miles in one hour.
Answer:
The domain is x ≥ -7
Step-by-step explanation:
The domain asks what values can x take
We know that the sqrt(x+7) must be ≥ 0
That means the smallest value it can be is zero
x+7 ≥ 0
x ≥ -7
The domain is x ≥ -7
For proportions just cross multiply.
8(y+2)=44
8y+16=44
8y=28
y=28/8