How do you solve $x^2 = 2x + 15$ ?

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Answer 1 · 2016-04-09T12:12:38

$x=-3$ or $x=5$

$x^2=2x+15$

$hArrx^2-2x-15=0$

Splitting the middle term in $-5x$ and $3x$ we get

$x^2-5x+3x-15=0$ or

$x(x-5)+3(x-5)=0$ or

$(x+3)(x-5)=0$

Hence $x=-3$ or $x=5$

How do you solve x^2 = 2x + 15x^2 = 2x + 15?