Question
I. y² + y – 56 = 0 II. 2x² + 11 x – 40 =
0Solution
I. y² + y – 56 = 0 y² + 8y - 7y – 56 = 0 y (y + 8) – 7(y + 8) = 0 y = 7, - 8 II. 2x² + 11 x – 40 = 0 2x² - 5 x + 16x – 40 = 0 x (2 x – 5) + 8 (2x – 5) = 0 (x + 8) (2 x – 5) = 0 x = - 8, 5/2 Hence, relationship cannot be established between x and y Alternate Method: Remember whenever roots of x & y are + & - both, there is no need to find the exact value of roots. In this case, there will be always no relation between x & y. Hence relationship between x & y cannot be established.
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