Answer is (a) side length of 6 ft and (b) yes it is a rational number
Step by step. A square has all equal sides (S), and the area is found by multiplying L x W, or S^2. So to reverse that, you know the area is 36, so you want the square root of 36 = 6.
Now, a rational number is any number that can be written as a fraction, so yes, 6 is a rational number.