How do you solve by completing the square $2x^2-6x-20=0$ ?

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Answer 1 · 2018-03-23T18:28:11

$x_1=-2$ and $x_2=5$

$2x^2-6x-20=0$

$2*(x^2-3x-10)=0$

$2*(x^2-3x+9/4-49/4)=0$

$2*((x-3/2)^2-(7/2)^2)=0$

$2(x-3/2+7/2)(x-3/2-7/2)=0$

$2(x+2)(x-5)=0$

Thus, $x_1=-2$ and $x_2=5$

How do you solve by completing the square 2x^2-6x-20=02x^2-6x-20=0?