Solve for x
x=2
x=\frac{2}{3}\approx 0.666666667
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6x-4=6x^{2}-10x+4
Combine -4x and -6x to get -10x.
6x-4-6x^{2}=-10x+4
Subtract 6x^{2} from both sides.
6x-4-6x^{2}+10x=4
Add 10x to both sides.
16x-4-6x^{2}=4
Combine 6x and 10x to get 16x.
16x-4-6x^{2}-4=0
Subtract 4 from both sides.
16x-8-6x^{2}=0
Subtract 4 from -4 to get -8.
8x-4-3x^{2}=0
Divide both sides by 2.
-3x^{2}+8x-4=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=8 ab=-3\left(-4\right)=12
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -3x^{2}+ax+bx-4. To find a and b, set up a system to be solved.
1,12 2,6 3,4
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 12.
1+12=13 2+6=8 3+4=7
Calculate the sum for each pair.
a=6 b=2
The solution is the pair that gives sum 8.
\left(-3x^{2}+6x\right)+\left(2x-4\right)
Rewrite -3x^{2}+8x-4 as \left(-3x^{2}+6x\right)+\left(2x-4\right).
3x\left(-x+2\right)-2\left(-x+2\right)
Factor out 3x in the first and -2 in the second group.
\left(-x+2\right)\left(3x-2\right)
Factor out common term -x+2 by using distributive property.
x=2 x=\frac{2}{3}
To find equation solutions, solve -x+2=0 and 3x-2=0.
6x-4=6x^{2}-10x+4
Combine -4x and -6x to get -10x.
6x-4-6x^{2}=-10x+4
Subtract 6x^{2} from both sides.
6x-4-6x^{2}+10x=4
Add 10x to both sides.
16x-4-6x^{2}=4
Combine 6x and 10x to get 16x.
16x-4-6x^{2}-4=0
Subtract 4 from both sides.
16x-8-6x^{2}=0
Subtract 4 from -4 to get -8.
-6x^{2}+16x-8=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{-16±\sqrt{16^{2}-4\left(-6\right)\left(-8\right)}}{2\left(-6\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -6 for a, 16 for b, and -8 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-16±\sqrt{256-4\left(-6\right)\left(-8\right)}}{2\left(-6\right)}
Square 16.
x=\frac{-16±\sqrt{256+24\left(-8\right)}}{2\left(-6\right)}
Multiply -4 times -6.
x=\frac{-16±\sqrt{256-192}}{2\left(-6\right)}
Multiply 24 times -8.
x=\frac{-16±\sqrt{64}}{2\left(-6\right)}
Add 256 to -192.
x=\frac{-16±8}{2\left(-6\right)}
Take the square root of 64.
x=\frac{-16±8}{-12}
Multiply 2 times -6.
x=-\frac{8}{-12}
Now solve the equation x=\frac{-16±8}{-12} when ± is plus. Add -16 to 8.
x=\frac{2}{3}
Reduce the fraction \frac{-8}{-12} to lowest terms by extracting and canceling out 4.
x=-\frac{24}{-12}
Now solve the equation x=\frac{-16±8}{-12} when ± is minus. Subtract 8 from -16.
x=2
Divide -24 by -12.
x=\frac{2}{3} x=2
The equation is now solved.
6x-4=6x^{2}-10x+4
Combine -4x and -6x to get -10x.
6x-4-6x^{2}=-10x+4
Subtract 6x^{2} from both sides.
6x-4-6x^{2}+10x=4
Add 10x to both sides.
16x-4-6x^{2}=4
Combine 6x and 10x to get 16x.
16x-6x^{2}=4+4
Add 4 to both sides.
16x-6x^{2}=8
Add 4 and 4 to get 8.
-6x^{2}+16x=8
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{-6x^{2}+16x}{-6}=\frac{8}{-6}
Divide both sides by -6.
x^{2}+\frac{16}{-6}x=\frac{8}{-6}
Dividing by -6 undoes the multiplication by -6.
x^{2}-\frac{8}{3}x=\frac{8}{-6}
Reduce the fraction \frac{16}{-6} to lowest terms by extracting and canceling out 2.
x^{2}-\frac{8}{3}x=-\frac{4}{3}
Reduce the fraction \frac{8}{-6} to lowest terms by extracting and canceling out 2.
x^{2}-\frac{8}{3}x+\left(-\frac{4}{3}\right)^{2}=-\frac{4}{3}+\left(-\frac{4}{3}\right)^{2}
Divide -\frac{8}{3}, the coefficient of the x term, by 2 to get -\frac{4}{3}. Then add the square of -\frac{4}{3} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{8}{3}x+\frac{16}{9}=-\frac{4}{3}+\frac{16}{9}
Square -\frac{4}{3} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{8}{3}x+\frac{16}{9}=\frac{4}{9}
Add -\frac{4}{3} to \frac{16}{9} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{4}{3}\right)^{2}=\frac{4}{9}
Factor x^{2}-\frac{8}{3}x+\frac{16}{9}. 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{4}{3}\right)^{2}}=\sqrt{\frac{4}{9}}
Take the square root of both sides of the equation.
x-\frac{4}{3}=\frac{2}{3} x-\frac{4}{3}=-\frac{2}{3}
Simplify.
x=2 x=\frac{2}{3}
Add \frac{4}{3} 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}