Question

$y = - {5}^{2} + 20x$
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Answer 1

$y = - 5 {}^{2} + 2 0x \\ 0 = - 5 {}^{2} + 20x \\ 0 = x - 5 + 20x \\ - 2x = - 25 \\ x = \frac{5}{4}$

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