Solve for x
x=11
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9x^{2}-6x-87=8x\left(x-2\right)+\left(x+1\right)^{2}
Use the distributive property to multiply 3x by 3x-2.
9x^{2}-6x-87=8x^{2}-16x+\left(x+1\right)^{2}
Use the distributive property to multiply 8x by x-2.
9x^{2}-6x-87=8x^{2}-16x+x^{2}+2x+1
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(x+1\right)^{2}.
9x^{2}-6x-87=9x^{2}-16x+2x+1
Combine 8x^{2} and x^{2} to get 9x^{2}.
9x^{2}-6x-87=9x^{2}-14x+1
Combine -16x and 2x to get -14x.
9x^{2}-6x-87-9x^{2}=-14x+1
Subtract 9x^{2} from both sides.
-6x-87=-14x+1
Combine 9x^{2} and -9x^{2} to get 0.
-6x-87+14x=1
Add 14x to both sides.
8x-87=1
Combine -6x and 14x to get 8x.
8x=1+87
Add 87 to both sides.
8x=88
Add 1 and 87 to get 88.
x=\frac{88}{8}
Divide both sides by 8.
x=11
Divide 88 by 8 to get 11.
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