SOLUTION: The length of a rectangle is 9 inches more than twice the width. If the area is to be at least 45 square inches, what are the possibilities for the width?

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Question 1160435: The length of a rectangle is 9 inches more than twice the width. If the area is to be at least 45 square inches, what are the possibilities for the width?
Answer by greenestamps(13209) About Me  (Show Source):
You can put this solution on YOUR website!


Let w be the width; then the length is 2w+9.

The area (length times width) is greater than or equal to 45 square inches:

w%282w%2B9%29%3E=45
2w%5E2%2B9w-45%3E=0
%28w-3%29%282w%2B15%29%3E=+0
w%3E=3 or w%3C=+-15%2F2

Clearly the negative solution makes no sense in the problem. So

ANSWER: The width can be anything 3 inches or greater

NOTE: That result can be obtained in a few seconds with a bit of trial and error and simple arithmetic....