since a rectangle is 2 triangles put together then just use the pythoragean therom to find the length of the rectange.a^2+b^2=c^2 60=c, b=36
a^2+36^2=60^2
a^2+1296=3600
a^2+1296-1296=3600-1296
a^2=2304
sq root of a^2=sq root of 2304
a=48
the missing length of the triangle is 48in