What is the answer for b and how did you get it ?

So for this we will be using the pythagorean theorem, which is  . The a and b variable stand for the legs of the triangle and c represents the hypotenuse.

So to start, replace a and c variable with 39 and 65. Your equation should look like this:  . From here we can solve.

Solve the exponents to get 

Subtract 1521 on each side to get 

Square root each side and your answer should be km