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A rectangular deck is 12ft by 14ft. When the length and width are increased by the same amount, the area becomes 288sq. ft. By how much were the dimensions increased?

User Chantee
by
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2 Answers

3 votes
its 16 by 18 so by 4 ft
User JuhaKangas
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1 vote

Dimensions of rectangle = 12 + x and 14 + x

(12 + x) (14 + x) = 288

x^2 + 26x + 168 = 288

x^2 + 26x - 120 = 0


(x + 30) (x - 4) = 0

x=-30, x =4

since 4 is positive

the dimensions increased by 4 feet

check the answer

12+4 = 16

14 +4 = 18

18*16 =288


User Ppovoski
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7.3k points