Solve for x
x=2
x=-2
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\frac{1}{9}x^{2}-\frac{4}{3}x+4=\left(x-\frac{2}{3}\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(\frac{1}{3}x-2\right)^{2}.
\frac{1}{9}x^{2}-\frac{4}{3}x+4=x^{2}-\frac{4}{3}x+\frac{4}{9}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-\frac{2}{3}\right)^{2}.
\frac{1}{9}x^{2}-\frac{4}{3}x+4-x^{2}=-\frac{4}{3}x+\frac{4}{9}
Subtract x^{2} from both sides.
-\frac{8}{9}x^{2}-\frac{4}{3}x+4=-\frac{4}{3}x+\frac{4}{9}
Combine \frac{1}{9}x^{2} and -x^{2} to get -\frac{8}{9}x^{2}.
-\frac{8}{9}x^{2}-\frac{4}{3}x+4+\frac{4}{3}x=\frac{4}{9}
Add \frac{4}{3}x to both sides.
-\frac{8}{9}x^{2}+4=\frac{4}{9}
Combine -\frac{4}{3}x and \frac{4}{3}x to get 0.
-\frac{8}{9}x^{2}=\frac{4}{9}-4
Subtract 4 from both sides.
-\frac{8}{9}x^{2}=-\frac{32}{9}
Subtract 4 from \frac{4}{9} to get -\frac{32}{9}.
x^{2}=-\frac{32}{9}\left(-\frac{9}{8}\right)
Multiply both sides by -\frac{9}{8}, the reciprocal of -\frac{8}{9}.
x^{2}=4
Multiply -\frac{32}{9} and -\frac{9}{8} to get 4.
x=2 x=-2
Take the square root of both sides of the equation.
\frac{1}{9}x^{2}-\frac{4}{3}x+4=\left(x-\frac{2}{3}\right)^{2}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(\frac{1}{3}x-2\right)^{2}.
\frac{1}{9}x^{2}-\frac{4}{3}x+4=x^{2}-\frac{4}{3}x+\frac{4}{9}
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-\frac{2}{3}\right)^{2}.
\frac{1}{9}x^{2}-\frac{4}{3}x+4-x^{2}=-\frac{4}{3}x+\frac{4}{9}
Subtract x^{2} from both sides.
-\frac{8}{9}x^{2}-\frac{4}{3}x+4=-\frac{4}{3}x+\frac{4}{9}
Combine \frac{1}{9}x^{2} and -x^{2} to get -\frac{8}{9}x^{2}.
-\frac{8}{9}x^{2}-\frac{4}{3}x+4+\frac{4}{3}x=\frac{4}{9}
Add \frac{4}{3}x to both sides.
-\frac{8}{9}x^{2}+4=\frac{4}{9}
Combine -\frac{4}{3}x and \frac{4}{3}x to get 0.
-\frac{8}{9}x^{2}+4-\frac{4}{9}=0
Subtract \frac{4}{9} from both sides.
-\frac{8}{9}x^{2}+\frac{32}{9}=0
Subtract \frac{4}{9} from 4 to get \frac{32}{9}.
x=\frac{0±\sqrt{0^{2}-4\left(-\frac{8}{9}\right)\times \frac{32}{9}}}{2\left(-\frac{8}{9}\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -\frac{8}{9} for a, 0 for b, and \frac{32}{9} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-\frac{8}{9}\right)\times \frac{32}{9}}}{2\left(-\frac{8}{9}\right)}
Square 0.
x=\frac{0±\sqrt{\frac{32}{9}\times \frac{32}{9}}}{2\left(-\frac{8}{9}\right)}
Multiply -4 times -\frac{8}{9}.
x=\frac{0±\sqrt{\frac{1024}{81}}}{2\left(-\frac{8}{9}\right)}
Multiply \frac{32}{9} times \frac{32}{9} by multiplying numerator times numerator and denominator times denominator. Then reduce the fraction to lowest terms if possible.
x=\frac{0±\frac{32}{9}}{2\left(-\frac{8}{9}\right)}
Take the square root of \frac{1024}{81}.
x=\frac{0±\frac{32}{9}}{-\frac{16}{9}}
Multiply 2 times -\frac{8}{9}.
x=-2
Now solve the equation x=\frac{0±\frac{32}{9}}{-\frac{16}{9}} when ± is plus.
x=2
Now solve the equation x=\frac{0±\frac{32}{9}}{-\frac{16}{9}} when ± is minus.
x=-2 x=2
The equation is now solved.
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