This question is and algebra question

Question

the width of a rectangular slab of concrete is 4 m less than the length. The area is 45 meters squared. What are the dimensions of the rectangle

Answer 1

Lw = L(L-4) = L^2 -4L = 45 m^2

L^2 -4L = 45

L^2 -4L -45 = 0 factor

(L-9)(L+5) = 0

Length = 9 meters Long

w = 5 meters wide