Solve by completing the square. -4x^(2) 16x=21 Solve by completing the square. $$-4x^2 + 16x = 21$$
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Step 1
To solve by completing the square, we first want the coefficient of the $x^2$ term to be 1. Divide the entire equation by -4: $$\frac{-4x^2}{-4} + \frac{16x}{-4} = \frac{21}{-4}$$ $$x^2 - 4x = -\frac{21}{4}$$ Show more…
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