How do you solve by completing the square: $x^2 +2x - 24 =0$ ?

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Answer 1 · 2015-04-03T01:26:52

Ad $24$ to both sides to clear the constant from the left side of the equation
$x^2 + 2x = 24$

Remember that $(x+1)^2 = x^2 + 2x +1$
so add $1$ to both sides in order to complete the square on the left side
$x^2+2x+1 = 24 +1$

$(x+1)^2 = 25$

Take the square root of both sides
$x+1= +-5$

Giving the solutions
$x= 4$ and $x=-6$

How do you solve by completing the square: x^2 +2x - 24 =0x^2 +2x - 24 =0?