Find the width of a rectangle with a perimeter of 90 cm and a length of 15 cm.

A rectangle is a four sided polygon with equal opposite sides and all angles equal to 90º.

Answer: The width of the rectangle is 30 cm.

Let's find the width of the rectangle.

Explanation:

Given perimeter (P) = 90 cm

Length ( l ) = 15 cm.

Let the width of the rectangle be w.

Formual to find the perimeter of rectangle is 2 (l + w) 

⇒ 90 = 2 (15 + w)

By dividing both the sides with 2, we get

⇒ (15 + w) = 45

⇒ w = 45 - 15

⇒ w = 30 cm

Thus, the width of the rectangle with a perimeter of 90 cm and a length of 15 cm is 30 cm.