Sunday, March 3, 2013

Rectangle Word Problem

Introduction to Rectangle:

A Rectangleis any quadrilateral with four right angles. The term "oblong" is occasionally used to refer to a non-square rectangle. A rectangle with vertexes ABCD would be denoted as  ABCD.

We shall work out some problems on rectangles


Rectangle word problem 1:


A rectangle has a perimeter of 120 meters and its length L is 2 times its width W. Calculate the dimensions W and L, and the area of the rectangle.

Solution to rectangle word problem 1:

The formula to find the perimeter of rectangle is

2 L + 2 W = 120

Now, we rewrite the statement, length L is 2 times its width “w” into a mathematical equation as follows,

L = 2 W

We substitute L in the equation 2 L + 2 W = 120 by 2 W.

2(2 W) + 2 W = 120

Expand and group like terms.

6 W = 120

Solve for W.

W = 20 meters

Use the equation L = 2 W to find L.

L = 2 W = 40 meters

Use the formula of the area.

Area = L W = 40 * 20 = 800 meters 2


Rectangle word problem 2:


The perimeter of a rectangle is 70 feet and its area is 304 feet 2. Find the length L and the width W of the rectangle, such that L > W.

Solution for rectangle word problem 2:

The formula for perimeter of a rectangle is given by

2 L + 2 W = 70

and the formula area of a rectangle is given by

L W = 304

Divide all terms in the equation 2 L + 2 W = 35 by 2 to obtain

L + W = 35

Solve the above for W

W = 35 - L

Substitute W by 35 - L in the equation L W = 304

L(35 - L) = 304

Expand the above equation and rewrite with right term equal to zero.

-L 2 + 35 L - 304 = 0

The above is a quadratic equation with two solutions.

L = 16 and L = 19

Use W = 35 - L to find the corresponding values of W.

W = 19 and W = 16

Since L > W, the rectangle has the dimensions

L = 19 feet and W = 16 feet.


Practice rectangle word problem 1:


The perimeter of a rectangle is 90 feet and its area is 504 feet 2. Find the length L and the width W of the rectangle, such that L > W.

Practice rectangle word problem 2:

A rectangle has a perimeter of 240 meters and its length L is 5 times its width W. Calculate the dimensions W and L, and the area of the rectangle

No comments:

Post a Comment