Solve for x
x=4
x=0
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12x^{2}-48x=0
Subtract 48x from both sides.
x\left(12x-48\right)=0
Factor out x.
x=0 x=4
To find equation solutions, solve x=0 and 12x-48=0.
12x^{2}-48x=0
Subtract 48x from both sides.
x=\frac{-\left(-48\right)±\sqrt{\left(-48\right)^{2}}}{2\times 12}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 12 for a, -48 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-48\right)±48}{2\times 12}
Take the square root of \left(-48\right)^{2}.
x=\frac{48±48}{2\times 12}
The opposite of -48 is 48.
x=\frac{48±48}{24}
Multiply 2 times 12.
x=\frac{96}{24}
Now solve the equation x=\frac{48±48}{24} when ± is plus. Add 48 to 48.
x=4
Divide 96 by 24.
x=\frac{0}{24}
Now solve the equation x=\frac{48±48}{24} when ± is minus. Subtract 48 from 48.
x=0
Divide 0 by 24.
x=4 x=0
The equation is now solved.
12x^{2}-48x=0
Subtract 48x from both sides.
\frac{12x^{2}-48x}{12}=\frac{0}{12}
Divide both sides by 12.
x^{2}+\left(-\frac{48}{12}\right)x=\frac{0}{12}
Dividing by 12 undoes the multiplication by 12.
x^{2}-4x=\frac{0}{12}
Divide -48 by 12.
x^{2}-4x=0
Divide 0 by 12.
x^{2}-4x+\left(-2\right)^{2}=\left(-2\right)^{2}
Divide -4, the coefficient of the x term, by 2 to get -2. Then add the square of -2 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-4x+4=4
Square -2.
\left(x-2\right)^{2}=4
Factor x^{2}-4x+4. 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-2\right)^{2}}=\sqrt{4}
Take the square root of both sides of the equation.
x-2=2 x-2=-2
Simplify.
x=4 x=0
Add 2 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}