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MATHS.. about Quadratic Equations in One Unknown (2)
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1) The dimensions of a rectangular picture are 16cmx 20cm. The picture is surrounded with a wooden frame of unifoem with. Of the are of the fram is 252cm2, find its width. Answer: 1) 3 cm
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1) The dimensions of a rectangular picture are 16cmx 20cm. The picture is surrounded with a wooden frame of unifoem with. Of the are of the fram is 252cm2, find its width. Let the width be x cm, (16 + 2x)(20 + 2x) - (16) ( 20) = 252 (8 + x)(10 + x) - 80 = 63 80 + 18x + x^2 - 80 = 63 x^2 + 18x - 63 = 0 (x + 21)(x - 3) = 0 x = -21(rejected) or x = 3 Answer: 1) 3 cm
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