Question
I.70x² - 143x + 72 = 0 II. 80 y² - 142y
+ 63 = 0Solution
I. 70x² - 143x + 72 = 0 70x² - 63x - 80 x + 72 = 0 7 x(10 x – 9) – 8(10 x – 9) = 0 (7x – 8) (10 x – 9) = 0 ∴ x = 9/10 ,8/7 II. 80 y² - 142y + 63 = 0 80 y² - 70 y - 72y + 63 = 0 10 y(8 y – 7) – 9(8 y – 7) = 0 (10 y – 9) (8 y – 7) = 0 ∴ y = 9/10 ,7/8 Hence, x ≥ y
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