Solve for x
x=2
x = \frac{9}{2} = 4\frac{1}{2} = 4.5
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2\left(x-3\right)^{2}=x
Multiply both sides of the equation by 2.
2\left(x^{2}-6x+9\right)=x
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-3\right)^{2}.
2x^{2}-12x+18=x
Use the distributive property to multiply 2 by x^{2}-6x+9.
2x^{2}-12x+18-x=0
Subtract x from both sides.
2x^{2}-13x+18=0
Combine -12x and -x to get -13x.
a+b=-13 ab=2\times 18=36
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 2x^{2}+ax+bx+18. To find a and b, set up a system to be solved.
-1,-36 -2,-18 -3,-12 -4,-9 -6,-6
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. List all such integer pairs that give product 36.
-1-36=-37 -2-18=-20 -3-12=-15 -4-9=-13 -6-6=-12
Calculate the sum for each pair.
a=-9 b=-4
The solution is the pair that gives sum -13.
\left(2x^{2}-9x\right)+\left(-4x+18\right)
Rewrite 2x^{2}-13x+18 as \left(2x^{2}-9x\right)+\left(-4x+18\right).
x\left(2x-9\right)-2\left(2x-9\right)
Factor out x in the first and -2 in the second group.
\left(2x-9\right)\left(x-2\right)
Factor out common term 2x-9 by using distributive property.
x=\frac{9}{2} x=2
To find equation solutions, solve 2x-9=0 and x-2=0.
2\left(x-3\right)^{2}=x
Multiply both sides of the equation by 2.
2\left(x^{2}-6x+9\right)=x
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-3\right)^{2}.
2x^{2}-12x+18=x
Use the distributive property to multiply 2 by x^{2}-6x+9.
2x^{2}-12x+18-x=0
Subtract x from both sides.
2x^{2}-13x+18=0
Combine -12x and -x to get -13x.
x=\frac{-\left(-13\right)±\sqrt{\left(-13\right)^{2}-4\times 2\times 18}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, -13 for b, and 18 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-13\right)±\sqrt{169-4\times 2\times 18}}{2\times 2}
Square -13.
x=\frac{-\left(-13\right)±\sqrt{169-8\times 18}}{2\times 2}
Multiply -4 times 2.
x=\frac{-\left(-13\right)±\sqrt{169-144}}{2\times 2}
Multiply -8 times 18.
x=\frac{-\left(-13\right)±\sqrt{25}}{2\times 2}
Add 169 to -144.
x=\frac{-\left(-13\right)±5}{2\times 2}
Take the square root of 25.
x=\frac{13±5}{2\times 2}
The opposite of -13 is 13.
x=\frac{13±5}{4}
Multiply 2 times 2.
x=\frac{18}{4}
Now solve the equation x=\frac{13±5}{4} when ± is plus. Add 13 to 5.
x=\frac{9}{2}
Reduce the fraction \frac{18}{4} to lowest terms by extracting and canceling out 2.
x=\frac{8}{4}
Now solve the equation x=\frac{13±5}{4} when ± is minus. Subtract 5 from 13.
x=2
Divide 8 by 4.
x=\frac{9}{2} x=2
The equation is now solved.
2\left(x-3\right)^{2}=x
Multiply both sides of the equation by 2.
2\left(x^{2}-6x+9\right)=x
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-3\right)^{2}.
2x^{2}-12x+18=x
Use the distributive property to multiply 2 by x^{2}-6x+9.
2x^{2}-12x+18-x=0
Subtract x from both sides.
2x^{2}-13x+18=0
Combine -12x and -x to get -13x.
2x^{2}-13x=-18
Subtract 18 from both sides. Anything subtracted from zero gives its negation.
\frac{2x^{2}-13x}{2}=-\frac{18}{2}
Divide both sides by 2.
x^{2}-\frac{13}{2}x=-\frac{18}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}-\frac{13}{2}x=-9
Divide -18 by 2.
x^{2}-\frac{13}{2}x+\left(-\frac{13}{4}\right)^{2}=-9+\left(-\frac{13}{4}\right)^{2}
Divide -\frac{13}{2}, the coefficient of the x term, by 2 to get -\frac{13}{4}. Then add the square of -\frac{13}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{13}{2}x+\frac{169}{16}=-9+\frac{169}{16}
Square -\frac{13}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{13}{2}x+\frac{169}{16}=\frac{25}{16}
Add -9 to \frac{169}{16}.
\left(x-\frac{13}{4}\right)^{2}=\frac{25}{16}
Factor x^{2}-\frac{13}{2}x+\frac{169}{16}. 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{13}{4}\right)^{2}}=\sqrt{\frac{25}{16}}
Take the square root of both sides of the equation.
x-\frac{13}{4}=\frac{5}{4} x-\frac{13}{4}=-\frac{5}{4}
Simplify.
x=\frac{9}{2} x=2
Add \frac{13}{4} 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}