Answer:
12
Step-by-step explanation:
Use the Pythagorean theorem which is a^2 + b^2 = c^2
c is hypotenuse and a and b are the legs
we need to find a^2 so
a^2 + 16^2 = 20^2
a^22 + 256 = 400
then subtract 256 from 400
a^2 = 144
square root 144
= 12
Width = W
Length = 3 times w = 3W
Area = length x width = 3W * W = 3W^2
