Answer:
1.0010353034
Step-by-step explanation:
Suppose that this person drives at r mph going to the mountains, and gets there in 12 hours. Returning, this person drives at (r+20) mph and gets home in 8 hours. We don't know the distance yet, but can solve for the initial speed, r, by setting
d = 12r = (r+20)(8). Solving for r, r=40 mph (going) and (40+20)mph = 60 mph (returning. Since d=12 r, d = (12 hrs)(40 mph) = 480 miles (answer).
The answer is h = 2A/(b1 + b2).
In order to find this, use all the methods for solving typically used in these types of equations. See the below example.
A = 1/2(b1 + b2)h ---> Multiply both sides by 2.
2A = (b1 + b2)h -----> Divide both sides by (b1 + b2)
2A/(b1 + b2) = h
