Question

The length of a rectangle is the sum of the width and 1. The area of the rectangle is 20 units. What is the width, in units, of the rectangle?

Answer 1

Width of the rectangle is 4 units

Step-by-step explanation:

• Step 1: Let the width of the rectangle be x. Then the length = x + 1. Find dimensions if area = 20 sq. units

Area of the rectangle = length × width

⇒ 20 = x (x + 1)

⇒ 20 = x² + x

⇒ x² + x - 20 = 0

⇒ x² + 5x - 4x - 20 = 0 (Using Product Sum rule to factorize)

⇒ x(x + 5) - 4(x + 5) = 0

⇒ (x + 5)(x - 4) = 0

⇒ x = -5, 4 (negative value is neglected)

x = 4