Question

the length of a rectangle plus its width is 18 cm the area is 80 square units. what are the length and width of the rectangle?

Answer 1

If two sides of a rectangle add up to 18cm and the area is 80 units squared then the length is 10cm, and the width is 8cm. If you add 10 and 8 together you get 18, and if you multiply those you get 80 units squared. Hope this helps!

Answer 2

If the width is w, then the length will 18-w. Therefore 80=w(18-w)

80 = 18w-w^2   w^2-18w+80 =0   Factor (w-8)(w-10)=0  then w-8=0, so w=8 and w-10=0 so w =10  If the width is 8, the length is 10. If the length is 10 the width is 8.