Solve for x
x=11
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x^{2}-x-20=\left(x+7\right)\left(x-6\right)
Use the distributive property to multiply x-5 by x+4 and combine like terms.
x^{2}-x-20=x^{2}+x-42
Use the distributive property to multiply x+7 by x-6 and combine like terms.
x^{2}-x-20-x^{2}=x-42
Subtract x^{2} from both sides.
-x-20=x-42
Combine x^{2} and -x^{2} to get 0.
-x-20-x=-42
Subtract x from both sides.
-2x-20=-42
Combine -x and -x to get -2x.
-2x=-42+20
Add 20 to both sides.
-2x=-22
Add -42 and 20 to get -22.
x=\frac{-22}{-2}
Divide both sides by -2.
x=11
Divide -22 by -2 to get 11.
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