How do you solve 8x^2+32x-24 by completing the square?

1 Answer
salamat
Mar 20, 2017

x = -2 +sqrt 7, -2 - sqrt 7

Explanation:

8 x^2 + 32 x - 24 =0

reduce coefficient x^2 to 1 by dividing with 8
x^2 +4x -3 = 0

consider coefficient of x and divide by 2 then make a parentesis and square them, then square the number in parentesis and deduct it in the equation.
(x + 2)^2 - (2)^2 - 3 = 0
(x + 2)^2 - 4 - 3 = 0
(x + 2)^2 - 7 = 0
(x + 2)^2 = 7
(x + 2) = +-sqrt 7
x = -2 +-sqrt 7

x = -2 +sqrt 7, -2 - sqrt 7

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