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The difference of squares of two numbers is 180. The square of the smaller number is 8 times the larger number. Find the two numbers. |
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Answer» Let the larger number = x Then the square of the smaller number = 8 times the larger number = 8x and the square of the larger number = x2 According to the question, x2 - 8x = 180 => x2 - 8x - 180 = 0 => x2 - 18x + 10x - 180 = 0 => x(x - 18) + 10(x - 18) = 0 => (x - 18) (x + 10) = 0 => x - 18 = 0 or x + 10 = 0 => x = 18 or x = -10 Thus, the larger number = 18 or -10 Then, the square of the smaller number = 8(18) or 8(-10) = 144 or -80 The square of a number can't be negative, so, the square of smaller number = 144 Hence, the smaller number = sqrt(144) = 12 The numbers are 12 and 18 |
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