SOLUTION: I have a word problem that I can't figure out. The problem reads a rectangle is 4 feet longer than it is wide, and its area is 77 square feet. Find its dimensions. Thanks if you c

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Question 153540This question is from textbook Intermediate Algebra
: I have a word problem that I can't figure out. The problem reads a rectangle is 4 feet longer than it is wide, and its area is 77 square feet. Find its dimensions.
Thanks if you can help! This question is from textbook Intermediate Algebra

Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
A rectangle has a length and width, L and W we'll call them.
You also know that the length is 4 feet longer than the width.
1.L=W%2B4
The area of the rectangle is given by the formula,
2.A%5Br%5D=L%2AW=77
Substitute eq. 1 into eq. 2 and solve for W.
2.L%2AW=77
%28W%2B4%29%28W%29=77
W%5E2%2B4W=77
W%5E2%2B4W-77=0
%28W%2B11%29%28W-7%29=0
Two solutions:
W%2B11=0
W=-11
Negative width doesn't make sense so we'll throw it out.
W-7=0
highlight%28W=7%29
from above,
L=W%2B4
highlight%28L=11%29