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X^2 =−8x−7 solve by rewriting the square

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I HOPE THIS HELPS

x=−7

x=−1

x

2

=−8x−7

Add 8x to both sides.

x

2

+8x=−7

Add 7 to both sides.

x

2

+8x+7=0

To solve the equation, factor x

2

+8x+7 using formula x

2

+(a+b)x+ab=(x+a)(x+b). To find a and b, set up a system to be solved.

a+b=8

ab=7

Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. The only such pair is the system solution.

a=1

b=7

Rewrite factored expression (x+a)(x+b) using the obtained values.

(x+1)(x+7)

To find equation solutions, solve x+1=0 and x+7=0.

x=−1

x=−7

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