Solve for x
x = \frac{4}{3} = 1\frac{1}{3} \approx 1.333333333
x=0
Graph
Share
Copied to clipboard
9x^{2}-12x+4=4
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(3x-2\right)^{2}.
9x^{2}-12x+4-4=0
Subtract 4 from both sides.
9x^{2}-12x=0
Subtract 4 from 4 to get 0.
x\left(9x-12\right)=0
Factor out x.
x=0 x=\frac{4}{3}
To find equation solutions, solve x=0 and 9x-12=0.
9x^{2}-12x+4=4
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(3x-2\right)^{2}.
9x^{2}-12x+4-4=0
Subtract 4 from both sides.
9x^{2}-12x=0
Subtract 4 from 4 to get 0.
x=\frac{-\left(-12\right)±\sqrt{\left(-12\right)^{2}}}{2\times 9}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 9 for a, -12 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-12\right)±12}{2\times 9}
Take the square root of \left(-12\right)^{2}.
x=\frac{12±12}{2\times 9}
The opposite of -12 is 12.
x=\frac{12±12}{18}
Multiply 2 times 9.
x=\frac{24}{18}
Now solve the equation x=\frac{12±12}{18} when ± is plus. Add 12 to 12.
x=\frac{4}{3}
Reduce the fraction \frac{24}{18} to lowest terms by extracting and canceling out 6.
x=\frac{0}{18}
Now solve the equation x=\frac{12±12}{18} when ± is minus. Subtract 12 from 12.
x=0
Divide 0 by 18.
x=\frac{4}{3} x=0
The equation is now solved.
9x^{2}-12x+4=4
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(3x-2\right)^{2}.
9x^{2}-12x=4-4
Subtract 4 from both sides.
9x^{2}-12x=0
Subtract 4 from 4 to get 0.
\frac{9x^{2}-12x}{9}=\frac{0}{9}
Divide both sides by 9.
x^{2}+\left(-\frac{12}{9}\right)x=\frac{0}{9}
Dividing by 9 undoes the multiplication by 9.
x^{2}-\frac{4}{3}x=\frac{0}{9}
Reduce the fraction \frac{-12}{9} to lowest terms by extracting and canceling out 3.
x^{2}-\frac{4}{3}x=0
Divide 0 by 9.
x^{2}-\frac{4}{3}x+\left(-\frac{2}{3}\right)^{2}=\left(-\frac{2}{3}\right)^{2}
Divide -\frac{4}{3}, the coefficient of the x term, by 2 to get -\frac{2}{3}. Then add the square of -\frac{2}{3} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{4}{3}x+\frac{4}{9}=\frac{4}{9}
Square -\frac{2}{3} by squaring both the numerator and the denominator of the fraction.
\left(x-\frac{2}{3}\right)^{2}=\frac{4}{9}
Factor x^{2}-\frac{4}{3}x+\frac{4}{9}. 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{2}{3}\right)^{2}}=\sqrt{\frac{4}{9}}
Take the square root of both sides of the equation.
x-\frac{2}{3}=\frac{2}{3} x-\frac{2}{3}=-\frac{2}{3}
Simplify.
x=\frac{4}{3} x=0
Add \frac{2}{3} to both sides of the equation.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}