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Question:
(x + 2) / (x - 3) = 42 (x + 7)
Solution:
(x +2 ) (x + 7) = 42 (x - 3)
x² + 7x + 2x + 14 = 42x - 126
x² + 9x + 14 = 42x - 126
x² + 9x + 14 - 42x + 126 = 0
x² - 33x + 140 = 0
x² - 28x - 5x + 140 = 0
Taking out common factors
x(x - 28) -5(x - 28) = 0
(x - 5) (x - 28) = 0
x -5 = 0
OR
x - 28 = 0
Either
x = 5
OR
x = 28
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