Question

Solve: 2x2-x = 21 {-7/2,3} {-3, 7/2}​

Answer 1

The answer is (-3,7/2)

Explanation:

`2 {x}^(2) - x - 21 = 0 \\ (2x - 7)(x + 3) = 0 \\ 2x - 7 = 0 \: \: \: or \: \: x + 3 = 0 \\ x = (7)/(2) \: \: and \: x = - 3`

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