Solve for x
x=4
x = \frac{9}{4} = 2\frac{1}{4} = 2.25
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4\left(x-3\right)^{2}=x
Multiply both sides of the equation by 4.
4\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}.
4x^{2}-24x+36=x
Use the distributive property to multiply 4 by x^{2}-6x+9.
4x^{2}-24x+36-x=0
Subtract x from both sides.
4x^{2}-25x+36=0
Combine -24x and -x to get -25x.
a+b=-25 ab=4\times 36=144
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 4x^{2}+ax+bx+36. To find a and b, set up a system to be solved.
-1,-144 -2,-72 -3,-48 -4,-36 -6,-24 -8,-18 -9,-16 -12,-12
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 144.
-1-144=-145 -2-72=-74 -3-48=-51 -4-36=-40 -6-24=-30 -8-18=-26 -9-16=-25 -12-12=-24
Calculate the sum for each pair.
a=-16 b=-9
The solution is the pair that gives sum -25.
\left(4x^{2}-16x\right)+\left(-9x+36\right)
Rewrite 4x^{2}-25x+36 as \left(4x^{2}-16x\right)+\left(-9x+36\right).
4x\left(x-4\right)-9\left(x-4\right)
Factor out 4x in the first and -9 in the second group.
\left(x-4\right)\left(4x-9\right)
Factor out common term x-4 by using distributive property.
x=4 x=\frac{9}{4}
To find equation solutions, solve x-4=0 and 4x-9=0.
4\left(x-3\right)^{2}=x
Multiply both sides of the equation by 4.
4\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}.
4x^{2}-24x+36=x
Use the distributive property to multiply 4 by x^{2}-6x+9.
4x^{2}-24x+36-x=0
Subtract x from both sides.
4x^{2}-25x+36=0
Combine -24x and -x to get -25x.
x=\frac{-\left(-25\right)±\sqrt{\left(-25\right)^{2}-4\times 4\times 36}}{2\times 4}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 4 for a, -25 for b, and 36 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-25\right)±\sqrt{625-4\times 4\times 36}}{2\times 4}
Square -25.
x=\frac{-\left(-25\right)±\sqrt{625-16\times 36}}{2\times 4}
Multiply -4 times 4.
x=\frac{-\left(-25\right)±\sqrt{625-576}}{2\times 4}
Multiply -16 times 36.
x=\frac{-\left(-25\right)±\sqrt{49}}{2\times 4}
Add 625 to -576.
x=\frac{-\left(-25\right)±7}{2\times 4}
Take the square root of 49.
x=\frac{25±7}{2\times 4}
The opposite of -25 is 25.
x=\frac{25±7}{8}
Multiply 2 times 4.
x=\frac{32}{8}
Now solve the equation x=\frac{25±7}{8} when ± is plus. Add 25 to 7.
x=4
Divide 32 by 8.
x=\frac{18}{8}
Now solve the equation x=\frac{25±7}{8} when ± is minus. Subtract 7 from 25.
x=\frac{9}{4}
Reduce the fraction \frac{18}{8} to lowest terms by extracting and canceling out 2.
x=4 x=\frac{9}{4}
The equation is now solved.
4\left(x-3\right)^{2}=x
Multiply both sides of the equation by 4.
4\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}.
4x^{2}-24x+36=x
Use the distributive property to multiply 4 by x^{2}-6x+9.
4x^{2}-24x+36-x=0
Subtract x from both sides.
4x^{2}-25x+36=0
Combine -24x and -x to get -25x.
4x^{2}-25x=-36
Subtract 36 from both sides. Anything subtracted from zero gives its negation.
\frac{4x^{2}-25x}{4}=-\frac{36}{4}
Divide both sides by 4.
x^{2}-\frac{25}{4}x=-\frac{36}{4}
Dividing by 4 undoes the multiplication by 4.
x^{2}-\frac{25}{4}x=-9
Divide -36 by 4.
x^{2}-\frac{25}{4}x+\left(-\frac{25}{8}\right)^{2}=-9+\left(-\frac{25}{8}\right)^{2}
Divide -\frac{25}{4}, the coefficient of the x term, by 2 to get -\frac{25}{8}. Then add the square of -\frac{25}{8} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{25}{4}x+\frac{625}{64}=-9+\frac{625}{64}
Square -\frac{25}{8} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{25}{4}x+\frac{625}{64}=\frac{49}{64}
Add -9 to \frac{625}{64}.
\left(x-\frac{25}{8}\right)^{2}=\frac{49}{64}
Factor x^{2}-\frac{25}{4}x+\frac{625}{64}. 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{25}{8}\right)^{2}}=\sqrt{\frac{49}{64}}
Take the square root of both sides of the equation.
x-\frac{25}{8}=\frac{7}{8} x-\frac{25}{8}=-\frac{7}{8}
Simplify.
x=4 x=\frac{9}{4}
Add \frac{25}{8} to both sides of the equation.
Examples
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{ 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}