Solve for x
x=\frac{1}{4}=0.25
x=0
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5x^{2}-8x+\left(3x+6\right)x=0
Use the distributive property to multiply 3 by x+2.
5x^{2}-8x+3x^{2}+6x=0
Use the distributive property to multiply 3x+6 by x.
8x^{2}-8x+6x=0
Combine 5x^{2} and 3x^{2} to get 8x^{2}.
8x^{2}-2x=0
Combine -8x and 6x to get -2x.
x\left(8x-2\right)=0
Factor out x.
x=0 x=\frac{1}{4}
To find equation solutions, solve x=0 and 8x-2=0.
5x^{2}-8x+\left(3x+6\right)x=0
Use the distributive property to multiply 3 by x+2.
5x^{2}-8x+3x^{2}+6x=0
Use the distributive property to multiply 3x+6 by x.
8x^{2}-8x+6x=0
Combine 5x^{2} and 3x^{2} to get 8x^{2}.
8x^{2}-2x=0
Combine -8x and 6x to get -2x.
x=\frac{-\left(-2\right)±\sqrt{\left(-2\right)^{2}}}{2\times 8}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 8 for a, -2 for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-2\right)±2}{2\times 8}
Take the square root of \left(-2\right)^{2}.
x=\frac{2±2}{2\times 8}
The opposite of -2 is 2.
x=\frac{2±2}{16}
Multiply 2 times 8.
x=\frac{4}{16}
Now solve the equation x=\frac{2±2}{16} when ± is plus. Add 2 to 2.
x=\frac{1}{4}
Reduce the fraction \frac{4}{16} to lowest terms by extracting and canceling out 4.
x=\frac{0}{16}
Now solve the equation x=\frac{2±2}{16} when ± is minus. Subtract 2 from 2.
x=0
Divide 0 by 16.
x=\frac{1}{4} x=0
The equation is now solved.
5x^{2}-8x+\left(3x+6\right)x=0
Use the distributive property to multiply 3 by x+2.
5x^{2}-8x+3x^{2}+6x=0
Use the distributive property to multiply 3x+6 by x.
8x^{2}-8x+6x=0
Combine 5x^{2} and 3x^{2} to get 8x^{2}.
8x^{2}-2x=0
Combine -8x and 6x to get -2x.
\frac{8x^{2}-2x}{8}=\frac{0}{8}
Divide both sides by 8.
x^{2}+\left(-\frac{2}{8}\right)x=\frac{0}{8}
Dividing by 8 undoes the multiplication by 8.
x^{2}-\frac{1}{4}x=\frac{0}{8}
Reduce the fraction \frac{-2}{8} to lowest terms by extracting and canceling out 2.
x^{2}-\frac{1}{4}x=0
Divide 0 by 8.
x^{2}-\frac{1}{4}x+\left(-\frac{1}{8}\right)^{2}=\left(-\frac{1}{8}\right)^{2}
Divide -\frac{1}{4}, the coefficient of the x term, by 2 to get -\frac{1}{8}. Then add the square of -\frac{1}{8} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{1}{4}x+\frac{1}{64}=\frac{1}{64}
Square -\frac{1}{8} by squaring both the numerator and the denominator of the fraction.
\left(x-\frac{1}{8}\right)^{2}=\frac{1}{64}
Factor x^{2}-\frac{1}{4}x+\frac{1}{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{1}{8}\right)^{2}}=\sqrt{\frac{1}{64}}
Take the square root of both sides of the equation.
x-\frac{1}{8}=\frac{1}{8} x-\frac{1}{8}=-\frac{1}{8}
Simplify.
x=\frac{1}{4} x=0
Add \frac{1}{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}