An oriental rug is 5 feet longer than it is wide. The area is 12 ft². To the nearest tenth of a foot, find its dimensions. x = width
x + 5 = length area of a rectangle is length x width x(x + 5) = 12 {area is length x width} x² + 5x = 12 {used distributive property} x² + 5x - 12 = 0 {subtracted 12 from both sides} a = 1, b = 5, c = -12 -b ± √b² - 4ac -------------------- = x {the quadratic formula} 2a -5 ± √5² - 4(1)(-12) ---------------------------- = x {substituted into the quadratic formula} 2(1) -5 ± √25 + 48 --------------------- = x {squared the 5 and multiplied} 2 -5 ± √73 ------------- = x {added 25 and 48} 2 -5 ± 8.5 ------------ = x {evaluated square root of 73} 2 -5 + 8.5 ------------ = x {dropped the -8.5, because width cannot be negative} 2 3.5 ------ = x {added -5 and 8.5} 2 x = 1.75 {divided} x + 5 = 6.75 {substituted 1.75, in for x, into x + 5} width ≈ 1.8 ft length ≈ 6.8 ft © Algebra House
1 Comment
5/21/2012 05:29:44 pm
i like your mathematical qualification regarding length and breadth of rug as it is determined by algebraic formula i surely use this during my carpet also.thanks
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