Right triangle A’s longer leg is 9 ft. less than 3 times the shorter leg’s length and has a perimeter of 90 ft.
Right triangle B has the same area as right triangle A, but the longer leg of right triangle B is 12 longer than the shorter leg.
Find the perimeter of triangle B to the nearest tenth of a foot. Explain your thinking, and show all of your work.
A:
h^2 = x^2 + (3x-9)^2
x + 3x-9 + h = 90
A is 15-36-39 (just a 5-12-13 scaled up by 3)
and has an area of 15*36/2 = 270
B: 1/2 * x(x+12) = 270
B is 18-30-√1224
so its perimeter is 48+6√34