1. Give a mathematical representation for the word problem.

let x be the width

x+8 be the length

2. Write all the givens from the word problem

length x+8 m

width x m

area 20sq.m

3. Formulate an equation based from all the givens you have.

so, area of a rectangle is length × width

and then the equation is (x+8)(x)=20

4. solve the equation you formulated

x+8(x)=20

x²+8x=20

x²+8x-20=0 this is a quadratic equation and solve for x and only use positive value of x.