How do i do this when i am given no numbers?

Question

A square is made so that its area is four times it perimeter. Find the length of the side of the square?

Answer 1

a = 4p

p = 2l + 2w

a = lw

In a square, l = w

lw = 4(2l + 2w)

w^2 = 4(2w + 2w)

w^2 = 16w

w^2 - 16w = 0

w(w - 16) = 0

w = 16

l = 16

Check:

a = 4p

p = 2l + 2w = 64

a = 16 x 16 = 256

a = 4p

256 = 4(64)

Yes!