Solve for x
x=\frac{\sqrt{13}-1}{6}\approx 0.434258546
x=\frac{-\sqrt{13}-1}{6}\approx -0.767591879
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\left(x-1\right)\left(x-1\right)=\left(2x+1\right)\left(2x+1\right)+\left(x-1\right)\left(2x+1\right)\times 3
Variable x cannot be equal to any of the values -\frac{1}{2},1 since division by zero is not defined. Multiply both sides of the equation by \left(x-1\right)\left(2x+1\right), the least common multiple of 2x+1,x-1.
\left(x-1\right)^{2}=\left(2x+1\right)\left(2x+1\right)+\left(x-1\right)\left(2x+1\right)\times 3
Multiply x-1 and x-1 to get \left(x-1\right)^{2}.
\left(x-1\right)^{2}=\left(2x+1\right)^{2}+\left(x-1\right)\left(2x+1\right)\times 3
Multiply 2x+1 and 2x+1 to get \left(2x+1\right)^{2}.
x^{2}-2x+1=\left(2x+1\right)^{2}+\left(x-1\right)\left(2x+1\right)\times 3
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-1\right)^{2}.
x^{2}-2x+1=4x^{2}+4x+1+\left(x-1\right)\left(2x+1\right)\times 3
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(2x+1\right)^{2}.
x^{2}-2x+1=4x^{2}+4x+1+\left(2x^{2}-x-1\right)\times 3
Use the distributive property to multiply x-1 by 2x+1 and combine like terms.
x^{2}-2x+1=4x^{2}+4x+1+6x^{2}-3x-3
Use the distributive property to multiply 2x^{2}-x-1 by 3.
x^{2}-2x+1=10x^{2}+4x+1-3x-3
Combine 4x^{2} and 6x^{2} to get 10x^{2}.
x^{2}-2x+1=10x^{2}+x+1-3
Combine 4x and -3x to get x.
x^{2}-2x+1=10x^{2}+x-2
Subtract 3 from 1 to get -2.
x^{2}-2x+1-10x^{2}=x-2
Subtract 10x^{2} from both sides.
-9x^{2}-2x+1=x-2
Combine x^{2} and -10x^{2} to get -9x^{2}.
-9x^{2}-2x+1-x=-2
Subtract x from both sides.
-9x^{2}-3x+1=-2
Combine -2x and -x to get -3x.
-9x^{2}-3x+1+2=0
Add 2 to both sides.
-9x^{2}-3x+3=0
Add 1 and 2 to get 3.
x=\frac{-\left(-3\right)±\sqrt{\left(-3\right)^{2}-4\left(-9\right)\times 3}}{2\left(-9\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -9 for a, -3 for b, and 3 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-3\right)±\sqrt{9-4\left(-9\right)\times 3}}{2\left(-9\right)}
Square -3.
x=\frac{-\left(-3\right)±\sqrt{9+36\times 3}}{2\left(-9\right)}
Multiply -4 times -9.
x=\frac{-\left(-3\right)±\sqrt{9+108}}{2\left(-9\right)}
Multiply 36 times 3.
x=\frac{-\left(-3\right)±\sqrt{117}}{2\left(-9\right)}
Add 9 to 108.
x=\frac{-\left(-3\right)±3\sqrt{13}}{2\left(-9\right)}
Take the square root of 117.
x=\frac{3±3\sqrt{13}}{2\left(-9\right)}
The opposite of -3 is 3.
x=\frac{3±3\sqrt{13}}{-18}
Multiply 2 times -9.
x=\frac{3\sqrt{13}+3}{-18}
Now solve the equation x=\frac{3±3\sqrt{13}}{-18} when ± is plus. Add 3 to 3\sqrt{13}.
x=\frac{-\sqrt{13}-1}{6}
Divide 3+3\sqrt{13} by -18.
x=\frac{3-3\sqrt{13}}{-18}
Now solve the equation x=\frac{3±3\sqrt{13}}{-18} when ± is minus. Subtract 3\sqrt{13} from 3.
x=\frac{\sqrt{13}-1}{6}
Divide 3-3\sqrt{13} by -18.
x=\frac{-\sqrt{13}-1}{6} x=\frac{\sqrt{13}-1}{6}
The equation is now solved.
\left(x-1\right)\left(x-1\right)=\left(2x+1\right)\left(2x+1\right)+\left(x-1\right)\left(2x+1\right)\times 3
Variable x cannot be equal to any of the values -\frac{1}{2},1 since division by zero is not defined. Multiply both sides of the equation by \left(x-1\right)\left(2x+1\right), the least common multiple of 2x+1,x-1.
\left(x-1\right)^{2}=\left(2x+1\right)\left(2x+1\right)+\left(x-1\right)\left(2x+1\right)\times 3
Multiply x-1 and x-1 to get \left(x-1\right)^{2}.
\left(x-1\right)^{2}=\left(2x+1\right)^{2}+\left(x-1\right)\left(2x+1\right)\times 3
Multiply 2x+1 and 2x+1 to get \left(2x+1\right)^{2}.
x^{2}-2x+1=\left(2x+1\right)^{2}+\left(x-1\right)\left(2x+1\right)\times 3
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-1\right)^{2}.
x^{2}-2x+1=4x^{2}+4x+1+\left(x-1\right)\left(2x+1\right)\times 3
Use binomial theorem \left(a+b\right)^{2}=a^{2}+2ab+b^{2} to expand \left(2x+1\right)^{2}.
x^{2}-2x+1=4x^{2}+4x+1+\left(2x^{2}-x-1\right)\times 3
Use the distributive property to multiply x-1 by 2x+1 and combine like terms.
x^{2}-2x+1=4x^{2}+4x+1+6x^{2}-3x-3
Use the distributive property to multiply 2x^{2}-x-1 by 3.
x^{2}-2x+1=10x^{2}+4x+1-3x-3
Combine 4x^{2} and 6x^{2} to get 10x^{2}.
x^{2}-2x+1=10x^{2}+x+1-3
Combine 4x and -3x to get x.
x^{2}-2x+1=10x^{2}+x-2
Subtract 3 from 1 to get -2.
x^{2}-2x+1-10x^{2}=x-2
Subtract 10x^{2} from both sides.
-9x^{2}-2x+1=x-2
Combine x^{2} and -10x^{2} to get -9x^{2}.
-9x^{2}-2x+1-x=-2
Subtract x from both sides.
-9x^{2}-3x+1=-2
Combine -2x and -x to get -3x.
-9x^{2}-3x=-2-1
Subtract 1 from both sides.
-9x^{2}-3x=-3
Subtract 1 from -2 to get -3.
\frac{-9x^{2}-3x}{-9}=-\frac{3}{-9}
Divide both sides by -9.
x^{2}+\left(-\frac{3}{-9}\right)x=-\frac{3}{-9}
Dividing by -9 undoes the multiplication by -9.
x^{2}+\frac{1}{3}x=-\frac{3}{-9}
Reduce the fraction \frac{-3}{-9} to lowest terms by extracting and canceling out 3.
x^{2}+\frac{1}{3}x=\frac{1}{3}
Reduce the fraction \frac{-3}{-9} to lowest terms by extracting and canceling out 3.
x^{2}+\frac{1}{3}x+\left(\frac{1}{6}\right)^{2}=\frac{1}{3}+\left(\frac{1}{6}\right)^{2}
Divide \frac{1}{3}, the coefficient of the x term, by 2 to get \frac{1}{6}. Then add the square of \frac{1}{6} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{1}{3}x+\frac{1}{36}=\frac{1}{3}+\frac{1}{36}
Square \frac{1}{6} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{1}{3}x+\frac{1}{36}=\frac{13}{36}
Add \frac{1}{3} to \frac{1}{36} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{1}{6}\right)^{2}=\frac{13}{36}
Factor x^{2}+\frac{1}{3}x+\frac{1}{36}. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(x+\frac{1}{6}\right)^{2}}=\sqrt{\frac{13}{36}}
Take the square root of both sides of the equation.
x+\frac{1}{6}=\frac{\sqrt{13}}{6} x+\frac{1}{6}=-\frac{\sqrt{13}}{6}
Simplify.
x=\frac{\sqrt{13}-1}{6} x=\frac{-\sqrt{13}-1}{6}
Subtract \frac{1}{6} from both sides of the equation.
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