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.