SOLUTION: The length of a rectangular sign is 3feet longer than the width. If the sign has a area of 40 square feet for advertising , find its length and its width.

Question 128350: The length of a rectangular sign is 3feet longer than the width. If the sign has a area of 40 square feet for advertising , find its length and its width.
Answer by chitra(359) (Show Source): You can put this solution on YOUR website!
Let "x" ft be the width of the rectangle

So lenght will be "3 + x" ft

Given area = 40 ft^2

We know that the area of the rectangle is given by lenght times breadth

40 = x * (x + 3)

40 = x^2 + 3x

==> x^2 + 3x - 40 = 0

==> by the method of factoring we find

==> x^2 + 8x - 5x - 40 = 0

==> x(x + 8) - 5(x + 8) = 0

==> x = 5 Or x = -8

We dont consider the negative values of x.

Therfore x = 5 ft will be the width

and x + 3 = 5 + 3 = 8ft will be the lenght of the rectangle

thus the solution
RELATED QUESTIONS
I am having problems with this, can someone please help me with this question? The... (answered by alka)

The length of a rectangular sign is 3 feet longer than the width. If the sign has an... (answered by checkley71)

I need help solving this problem. The length of a rectangular sign is 3 feet longer... (answered by pwac)

The length of a rectangular sign is 5 feet longer than the width. If the sign�s area is... (answered by lwsshak3)

The length of a rectangular sign is 3 feet longer than the width. If the sign's area is... (answered by bucky)

The length of a rectangular sign is 4 feet longer than the width. If the sign's area is... (answered by rothauserc)

If the length of a rectangle sign is to be 2 feet longer than the width and the area is... (answered by drk,unlockmath)

The length of a rectangular sign is 2 meters less than 3 times its width. If the area of... (answered by Cromlix)

A rectangular billboard sign has a length that is four yards longer than twice its width, (answered by MathLover1,ikleyn)