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(PLEASE HELP ME ASAP

a) The length of a rectangle is 3 m longer than its width and the area of the rectangle is 108 m². Find its length.​

User Eli Sander
by
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1 Answer

1 vote
Draw a rectangle. If the length is 3 inches longer than its width, we can write the width as "w" and the length as the width + 3
Area is (width)(Length) = (width)(width+3)

W
----------
| |
| |
| | L = w+3
| |
| |
-----------

A = (w+3)(w)
A = w2 + 3w = 108.
(Problem states that area is 108 sq in)

Need to solve this quadratic equation

w2 + 3y - 108 = 0

Factor:
(w - 9) (w + 12) = 0

So
w - 9 = 0. or. w + 12 = 0

Solve these and get
w = 9. or. w = -12

Only one that makes sense in real life is the poitive one.

So the dimensions are

Width = 9 inches
Length = 12 inches
User Norym
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