Solve for x
x = -\frac{13}{3} = -4\frac{1}{3} \approx -4.333333333
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x^{2}-4x-21=x\left(x+2\right)+5
Use the distributive property to multiply x-7 by x+3 and combine like terms.
x^{2}-4x-21=x^{2}+2x+5
Use the distributive property to multiply x by x+2.
x^{2}-4x-21-x^{2}=2x+5
Subtract x^{2} from both sides.
-4x-21=2x+5
Combine x^{2} and -x^{2} to get 0.
-4x-21-2x=5
Subtract 2x from both sides.
-6x-21=5
Combine -4x and -2x to get -6x.
-6x=5+21
Add 21 to both sides.
-6x=26
Add 5 and 21 to get 26.
x=\frac{26}{-6}
Divide both sides by -6.
x=-\frac{13}{3}
Reduce the fraction \frac{26}{-6} to lowest terms by extracting and canceling out 2.
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