A) find the distance of each of the courses. (round any distances to the nearest tenth, if necessary) b) determine if coach larter lengthened the course. c) determine how much larger or smaller the new course is.

In your topic, you NEED to memorize a^2+b^2=c^2.

For current, the area is 60 kilo sq. and one side is 5.
To find the area it's length times width, so what 5 (assume a) times what equals 60? 12 (assume b)
To find the hypotenuse, 5^2+12^2=c^2. 25+144=c^2. 169=c^2. c=13
Add up the sides and you get 30 kilometers for current.

For prepared, a and b is given, so:
9^2 is 81. 81+81=c^2. 162=c^2. 12.727=c
9+9+12.727=30.727=30.7 (nearest tenth) kilometers

Coach Larter lengthened the course by .7 kilometers.

The correct answer for the question that is being presented above is this one: "A.34.41." The information given represents lengths of sides of a right triangle with c the hypotenuse. 

h^2 = a^2 + b^2
c^2 = 20^2 + 28^2
c^2 = 400 + 784
c^2 = 1184
c = 34.41