The length of a photograph is 3 cm less than twice the width. the area is 77cm². find the dimensions of the photograph . x = width 2x  3 = length {length is 3 less than twice width} Area of a rectangle is width x length x(2x  3) = 77 {area is width x length} 2x²  3x = 77 {used distributive property} 2x²  3x  77 = 0 {subtracted 77 from both sides} (2x + 11)(x  7) = 0 {factored into two binomials} 2x + 11 = 0 or x  7 = 0 {set each factor equal to 0} 2x = 11 or x = 7 {subtracted 11 and added 7} x = 11/2 or x = 7 {divided first equation by 2} x = 7 {width cannot be negative} 2x  3 = 11 {substituted 7, in for x, into 2x  3} width = 7 cm length = 11 cm  Algebra House
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