Question

The area of a rectangle is 28 m', and the length of the rectangle is 1 m more than twice the width. Find the dimensions of the rectangle.

Answer 1

8m ×3.5m

Explanation:

Area of rectangle= length ×width

Let the length and width of the rectangle be L and W meters respectively.

Area of rectangle= LW

LW= 28 -----(1)

L= 2W +1 -----(2)

Subst. (2) into (1):

(2W +1)(W)= 28

Expand:

2W² +W= 28

-28 on both sides:

2W² +W -28= 0

Factorise:

(W +4)(2W -7)= 0

W +4=0 or 2W -7=0

W= -4 (reject) or W= 3.5

Substitute W= 3.5 into (2):

L= 2(3.5) +1

L= 7 +1

L= 8

∴ The dimensions of the rectangle is 8m ×3.5m.