Solve for x
x = -\frac{3}{2} = -1\frac{1}{2} = -1.5
x=1
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2x-4x^{2}+6=4x
Use the distributive property to multiply 2x+2 by 3-2x and combine like terms.
2x-4x^{2}+6-4x=0
Subtract 4x from both sides.
-2x-4x^{2}+6=0
Combine 2x and -4x to get -2x.
-x-2x^{2}+3=0
Divide both sides by 2.
-2x^{2}-x+3=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=-1 ab=-2\times 3=-6
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -2x^{2}+ax+bx+3. To find a and b, set up a system to be solved.
1,-6 2,-3
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product -6.
1-6=-5 2-3=-1
Calculate the sum for each pair.
a=2 b=-3
The solution is the pair that gives sum -1.
\left(-2x^{2}+2x\right)+\left(-3x+3\right)
Rewrite -2x^{2}-x+3 as \left(-2x^{2}+2x\right)+\left(-3x+3\right).
2x\left(-x+1\right)+3\left(-x+1\right)
Factor out 2x in the first and 3 in the second group.
\left(-x+1\right)\left(2x+3\right)
Factor out common term -x+1 by using distributive property.
x=1 x=-\frac{3}{2}
To find equation solutions, solve -x+1=0 and 2x+3=0.
2x-4x^{2}+6=4x
Use the distributive property to multiply 2x+2 by 3-2x and combine like terms.
2x-4x^{2}+6-4x=0
Subtract 4x from both sides.
-2x-4x^{2}+6=0
Combine 2x and -4x to get -2x.
-4x^{2}-2x+6=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{-\left(-2\right)±\sqrt{\left(-2\right)^{2}-4\left(-4\right)\times 6}}{2\left(-4\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -4 for a, -2 for b, and 6 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-2\right)±\sqrt{4-4\left(-4\right)\times 6}}{2\left(-4\right)}
Square -2.
x=\frac{-\left(-2\right)±\sqrt{4+16\times 6}}{2\left(-4\right)}
Multiply -4 times -4.
x=\frac{-\left(-2\right)±\sqrt{4+96}}{2\left(-4\right)}
Multiply 16 times 6.
x=\frac{-\left(-2\right)±\sqrt{100}}{2\left(-4\right)}
Add 4 to 96.
x=\frac{-\left(-2\right)±10}{2\left(-4\right)}
Take the square root of 100.
x=\frac{2±10}{2\left(-4\right)}
The opposite of -2 is 2.
x=\frac{2±10}{-8}
Multiply 2 times -4.
x=\frac{12}{-8}
Now solve the equation x=\frac{2±10}{-8} when ± is plus. Add 2 to 10.
x=-\frac{3}{2}
Reduce the fraction \frac{12}{-8} to lowest terms by extracting and canceling out 4.
x=-\frac{8}{-8}
Now solve the equation x=\frac{2±10}{-8} when ± is minus. Subtract 10 from 2.
x=1
Divide -8 by -8.
x=-\frac{3}{2} x=1
The equation is now solved.
2x-4x^{2}+6=4x
Use the distributive property to multiply 2x+2 by 3-2x and combine like terms.
2x-4x^{2}+6-4x=0
Subtract 4x from both sides.
-2x-4x^{2}+6=0
Combine 2x and -4x to get -2x.
-2x-4x^{2}=-6
Subtract 6 from both sides. Anything subtracted from zero gives its negation.
-4x^{2}-2x=-6
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{-4x^{2}-2x}{-4}=-\frac{6}{-4}
Divide both sides by -4.
x^{2}+\left(-\frac{2}{-4}\right)x=-\frac{6}{-4}
Dividing by -4 undoes the multiplication by -4.
x^{2}+\frac{1}{2}x=-\frac{6}{-4}
Reduce the fraction \frac{-2}{-4} to lowest terms by extracting and canceling out 2.
x^{2}+\frac{1}{2}x=\frac{3}{2}
Reduce the fraction \frac{-6}{-4} to lowest terms by extracting and canceling out 2.
x^{2}+\frac{1}{2}x+\left(\frac{1}{4}\right)^{2}=\frac{3}{2}+\left(\frac{1}{4}\right)^{2}
Divide \frac{1}{2}, the coefficient of the x term, by 2 to get \frac{1}{4}. Then add the square of \frac{1}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{1}{2}x+\frac{1}{16}=\frac{3}{2}+\frac{1}{16}
Square \frac{1}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{1}{2}x+\frac{1}{16}=\frac{25}{16}
Add \frac{3}{2} to \frac{1}{16} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{1}{4}\right)^{2}=\frac{25}{16}
Factor x^{2}+\frac{1}{2}x+\frac{1}{16}. 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}{4}\right)^{2}}=\sqrt{\frac{25}{16}}
Take the square root of both sides of the equation.
x+\frac{1}{4}=\frac{5}{4} x+\frac{1}{4}=-\frac{5}{4}
Simplify.
x=1 x=-\frac{3}{2}
Subtract \frac{1}{4} from 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}