Solve for x
x = \frac{16}{9} = 1\frac{7}{9} \approx 1.777777778
x=0
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9x^{2}-12x+4=4\left(x+1\right)
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(3x-2\right)^{2}.
9x^{2}-12x+4=4x+4
Use the distributive property to multiply 4 by x+1.
9x^{2}-12x+4-4x=4
Subtract 4x from both sides.
9x^{2}-16x+4=4
Combine -12x and -4x to get -16x.
9x^{2}-16x+4-4=0
Subtract 4 from both sides.
9x^{2}-16x=0
Subtract 4 from 4 to get 0.
x\left(9x-16\right)=0
Factor out x.
x=0 x=\frac{16}{9}
To find equation solutions, solve x=0 and 9x-16=0.
9x^{2}-12x+4=4\left(x+1\right)
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(3x-2\right)^{2}.
9x^{2}-12x+4=4x+4
Use the distributive property to multiply 4 by x+1.
9x^{2}-12x+4-4x=4
Subtract 4x from both sides.
9x^{2}-16x+4=4
Combine -12x and -4x to get -16x.
9x^{2}-16x+4-4=0
Subtract 4 from both sides.
9x^{2}-16x=0
Subtract 4 from 4 to get 0.
x=\frac{-\left(-16\right)±\sqrt{\left(-16\right)^{2}}}{2\times 9}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 9 for a, -16 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-16\right)±16}{2\times 9}
Take the square root of \left(-16\right)^{2}.
x=\frac{16±16}{2\times 9}
The opposite of -16 is 16.
x=\frac{16±16}{18}
Multiply 2 times 9.
x=\frac{32}{18}
Now solve the equation x=\frac{16±16}{18} when ± is plus. Add 16 to 16.
x=\frac{16}{9}
Reduce the fraction \frac{32}{18} to lowest terms by extracting and canceling out 2.
x=\frac{0}{18}
Now solve the equation x=\frac{16±16}{18} when ± is minus. Subtract 16 from 16.
x=0
Divide 0 by 18.
x=\frac{16}{9} x=0
The equation is now solved.
9x^{2}-12x+4=4\left(x+1\right)
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(3x-2\right)^{2}.
9x^{2}-12x+4=4x+4
Use the distributive property to multiply 4 by x+1.
9x^{2}-12x+4-4x=4
Subtract 4x from both sides.
9x^{2}-16x+4=4
Combine -12x and -4x to get -16x.
9x^{2}-16x=4-4
Subtract 4 from both sides.
9x^{2}-16x=0
Subtract 4 from 4 to get 0.
\frac{9x^{2}-16x}{9}=\frac{0}{9}
Divide both sides by 9.
x^{2}-\frac{16}{9}x=\frac{0}{9}
Dividing by 9 undoes the multiplication by 9.
x^{2}-\frac{16}{9}x=0
Divide 0 by 9.
x^{2}-\frac{16}{9}x+\left(-\frac{8}{9}\right)^{2}=\left(-\frac{8}{9}\right)^{2}
Divide -\frac{16}{9}, the coefficient of the x term, by 2 to get -\frac{8}{9}. Then add the square of -\frac{8}{9} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{16}{9}x+\frac{64}{81}=\frac{64}{81}
Square -\frac{8}{9} by squaring both the numerator and the denominator of the fraction.
\left(x-\frac{8}{9}\right)^{2}=\frac{64}{81}
Factor x^{2}-\frac{16}{9}x+\frac{64}{81}. 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{8}{9}\right)^{2}}=\sqrt{\frac{64}{81}}
Take the square root of both sides of the equation.
x-\frac{8}{9}=\frac{8}{9} x-\frac{8}{9}=-\frac{8}{9}
Simplify.
x=\frac{16}{9} x=0
Add \frac{8}{9} to both sides of the equation.
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Simultaneous equation
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Limits
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