Question

You and your friend are standing back-to-back. Your friend runs 16 feet forward and then 12 feet right. At the same time, you run 12 feet forward and then 9 feet right. You stop and throw a baseball to your friend, who catches it. How far did you throw the baseball?

Answer 1

Add 16+12 to get 28.
Add 9+12 to get 21.

Think of these as the sides of a triangle.
a^2+b^2=c^2
28^2+21^2=1225
√1225=35

You threw the ball 35 feet.