SOLUTION: How do I solve the polynomial equation: (x+2)(x-7)=-18

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Question 409458: How do I solve the polynomial equation:
(x+2)(x-7)=-18

Answer by ewatrrr(24785)   (Show Source): You can put this solution on YOUR website!

Hi
solving
(x+2)(x-7)= -18 |(x+2)(x-7) = x(x-7)+2(x-7) = x^2 -7x +2x -14
x^2 -5x - 14 = -18
(x -5/2)^2 - 25/4 -14 = -18 |completing the square
(x -5/2)^2 = -4 + 25/4
(x-5/2)^2 = 2.25 |taking square root of both sides of eequation
x - 5/2 = ± 1.5
x = 5/2 ± 3/2
x = 4
x = 1
CHECKING our Answer(s)***
(x+2)(x-7)= -18
6*-3 = -18
3*-6 = -18

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