Answer: x = -1, -7
Set the polynomial to standard form: ax² + bx + c (already given).
x² + 8x + 7 = 0
Factor the polynomial. To do this, find two numbers that multiply to get c and add together to get b. In this case, those two numbers are 1 and 7.
(x + 1)(x + 7) = 0
Set each factor equal to zero and solve for x. The factors in the equation are (x + 1) and (x + 7).
x = -1
x = -7
The solutions to x² + 8x + 7 are -1 and -7. You can check this by using FOIL.
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O utside
I nside
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