Solve for x
x=46
x=0
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46x-x^{2}=0
Subtract x^{2} from both sides.
x\left(46-x\right)=0
Factor out x.
x=0 x=46
To find equation solutions, solve x=0 and 46-x=0.
46x-x^{2}=0
Subtract x^{2} from both sides.
-x^{2}+46x=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-46±\sqrt{46^{2}}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 46 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-46±46}{2\left(-1\right)}
Take the square root of 46^{2}.
x=\frac{-46±46}{-2}
Multiply 2 times -1.
x=\frac{0}{-2}
Now solve the equation x=\frac{-46±46}{-2} when ± is plus. Add -46 to 46.
x=0
Divide 0 by -2.
x=-\frac{92}{-2}
Now solve the equation x=\frac{-46±46}{-2} when ± is minus. Subtract 46 from -46.
x=46
Divide -92 by -2.
x=0 x=46
The equation is now solved.
46x-x^{2}=0
Subtract x^{2} from both sides.
-x^{2}+46x=0
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
\frac{-x^{2}+46x}{-1}=\frac{0}{-1}
Divide both sides by -1.
x^{2}+\frac{46}{-1}x=\frac{0}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}-46x=\frac{0}{-1}
Divide 46 by -1.
x^{2}-46x=0
Divide 0 by -1.
x^{2}-46x+\left(-23\right)^{2}=\left(-23\right)^{2}
Divide -46, the coefficient of the x term, by 2 to get -23. Then add the square of -23 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-46x+529=529
Square -23.
\left(x-23\right)^{2}=529
Factor x^{2}-46x+529. 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-23\right)^{2}}=\sqrt{529}
Take the square root of both sides of the equation.
x-23=23 x-23=-23
Simplify.
x=46 x=0
Add 23 to both sides of the equation.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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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}