As you can see this is not factorable in your head or obvious so we have to use the Quadratic Formula:
for Ax^2 + Bx + C = 0
x = ( -B / 2 A ) + or - ( sqrt (B ^ 2 - 4 x A x C) ) / 2 A
So A = 1, B = 8, C = -2
-8/ 2 + or - sqrt( 64- (4 x 1 x -2)) / 2
-4 + or - Sqrt( 72 ) / 2
-4 + or - 6 sqrt (2) / 2
-4 + or - 3 sqrt (2)
x = -4 + 3 sqrt (2) and -4 - Sqrt(2)
(x+4)^2=18. (x+4)(x+4)-18= x^2+8x-2=0. (x )(x )I have no idea how to factor this because no factors of two will add up to 48. Can you offer an explanation and tips on factoring this sort of question?
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