Solve for x
x=2
x=-\frac{1}{2}=-0.5
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4x^{2}-3x\left(2x-1\right)=-2
Multiply both sides of the equation by 2.
4x^{2}-6x^{2}+3x=-2
Use the distributive property to multiply -3x by 2x-1.
-2x^{2}+3x=-2
Combine 4x^{2} and -6x^{2} to get -2x^{2}.
-2x^{2}+3x+2=0
Add 2 to both sides.
a+b=3 ab=-2\times 2=-4
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -2x^{2}+ax+bx+2. To find a and b, set up a system to be solved.
-1,4 -2,2
Since ab is negative, a and b have the opposite signs. Since a+b is positive, the positive number has greater absolute value than the negative. List all such integer pairs that give product -4.
-1+4=3 -2+2=0
Calculate the sum for each pair.
a=4 b=-1
The solution is the pair that gives sum 3.
\left(-2x^{2}+4x\right)+\left(-x+2\right)
Rewrite -2x^{2}+3x+2 as \left(-2x^{2}+4x\right)+\left(-x+2\right).
2x\left(-x+2\right)-x+2
Factor out 2x in -2x^{2}+4x.
\left(-x+2\right)\left(2x+1\right)
Factor out common term -x+2 by using distributive property.
x=2 x=-\frac{1}{2}
To find equation solutions, solve -x+2=0 and 2x+1=0.
4x^{2}-3x\left(2x-1\right)=-2
Multiply both sides of the equation by 2.
4x^{2}-6x^{2}+3x=-2
Use the distributive property to multiply -3x by 2x-1.
-2x^{2}+3x=-2
Combine 4x^{2} and -6x^{2} to get -2x^{2}.
-2x^{2}+3x+2=0
Add 2 to both sides.
x=\frac{-3±\sqrt{3^{2}-4\left(-2\right)\times 2}}{2\left(-2\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -2 for a, 3 for b, and 2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-3±\sqrt{9-4\left(-2\right)\times 2}}{2\left(-2\right)}
Square 3.
x=\frac{-3±\sqrt{9+8\times 2}}{2\left(-2\right)}
Multiply -4 times -2.
x=\frac{-3±\sqrt{9+16}}{2\left(-2\right)}
Multiply 8 times 2.
x=\frac{-3±\sqrt{25}}{2\left(-2\right)}
Add 9 to 16.
x=\frac{-3±5}{2\left(-2\right)}
Take the square root of 25.
x=\frac{-3±5}{-4}
Multiply 2 times -2.
x=\frac{2}{-4}
Now solve the equation x=\frac{-3±5}{-4} when ± is plus. Add -3 to 5.
x=-\frac{1}{2}
Reduce the fraction \frac{2}{-4} to lowest terms by extracting and canceling out 2.
x=-\frac{8}{-4}
Now solve the equation x=\frac{-3±5}{-4} when ± is minus. Subtract 5 from -3.
x=2
Divide -8 by -4.
x=-\frac{1}{2} x=2
The equation is now solved.
4x^{2}-3x\left(2x-1\right)=-2
Multiply both sides of the equation by 2.
4x^{2}-6x^{2}+3x=-2
Use the distributive property to multiply -3x by 2x-1.
-2x^{2}+3x=-2
Combine 4x^{2} and -6x^{2} to get -2x^{2}.
\frac{-2x^{2}+3x}{-2}=-\frac{2}{-2}
Divide both sides by -2.
x^{2}+\frac{3}{-2}x=-\frac{2}{-2}
Dividing by -2 undoes the multiplication by -2.
x^{2}-\frac{3}{2}x=-\frac{2}{-2}
Divide 3 by -2.
x^{2}-\frac{3}{2}x=1
Divide -2 by -2.
x^{2}-\frac{3}{2}x+\left(-\frac{3}{4}\right)^{2}=1+\left(-\frac{3}{4}\right)^{2}
Divide -\frac{3}{2}, the coefficient of the x term, by 2 to get -\frac{3}{4}. Then add the square of -\frac{3}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{3}{2}x+\frac{9}{16}=1+\frac{9}{16}
Square -\frac{3}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{3}{2}x+\frac{9}{16}=\frac{25}{16}
Add 1 to \frac{9}{16}.
\left(x-\frac{3}{4}\right)^{2}=\frac{25}{16}
Factor x^{2}-\frac{3}{2}x+\frac{9}{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{3}{4}\right)^{2}}=\sqrt{\frac{25}{16}}
Take the square root of both sides of the equation.
x-\frac{3}{4}=\frac{5}{4} x-\frac{3}{4}=-\frac{5}{4}
Simplify.
x=2 x=-\frac{1}{2}
Add \frac{3}{4} 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}