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2x^{2}-6x=-4
Subtract 6x from both sides.
2x^{2}-6x+4=0
Add 4 to both sides.
x^{2}-3x+2=0
Divide both sides by 2.
a+b=-3 ab=1\times 2=2
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx+2. To find a and b, set up a system to be solved.
a=-2 b=-1
Since ab is positive, a and b have the same sign. Since a+b is negative, a and b are both negative. The only such pair is the system solution.
\left(x^{2}-2x\right)+\left(-x+2\right)
Rewrite x^{2}-3x+2 as \left(x^{2}-2x\right)+\left(-x+2\right).
x\left(x-2\right)-\left(x-2\right)
Factor out x in the first and -1 in the second group.
\left(x-2\right)\left(x-1\right)
Factor out common term x-2 by using distributive property.
x=2 x=1
To find equation solutions, solve x-2=0 and x-1=0.
2x^{2}-6x=-4
Subtract 6x from both sides.
2x^{2}-6x+4=0
Add 4 to both sides.
x=\frac{-\left(-6\right)±\sqrt{\left(-6\right)^{2}-4\times 2\times 4}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, -6 for b, and 4 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-6\right)±\sqrt{36-4\times 2\times 4}}{2\times 2}
Square -6.
x=\frac{-\left(-6\right)±\sqrt{36-8\times 4}}{2\times 2}
Multiply -4 times 2.
x=\frac{-\left(-6\right)±\sqrt{36-32}}{2\times 2}
Multiply -8 times 4.
x=\frac{-\left(-6\right)±\sqrt{4}}{2\times 2}
Add 36 to -32.
x=\frac{-\left(-6\right)±2}{2\times 2}
Take the square root of 4.
x=\frac{6±2}{2\times 2}
The opposite of -6 is 6.
x=\frac{6±2}{4}
Multiply 2 times 2.
x=\frac{8}{4}
Now solve the equation x=\frac{6±2}{4} when ± is plus. Add 6 to 2.
x=2
Divide 8 by 4.
x=\frac{4}{4}
Now solve the equation x=\frac{6±2}{4} when ± is minus. Subtract 2 from 6.
x=1
Divide 4 by 4.
x=2 x=1
The equation is now solved.
2x^{2}-6x=-4
Subtract 6x from both sides.
\frac{2x^{2}-6x}{2}=-\frac{4}{2}
Divide both sides by 2.
x^{2}+\left(-\frac{6}{2}\right)x=-\frac{4}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}-3x=-\frac{4}{2}
Divide -6 by 2.
x^{2}-3x=-2
Divide -4 by 2.
x^{2}-3x+\left(-\frac{3}{2}\right)^{2}=-2+\left(-\frac{3}{2}\right)^{2}
Divide -3, the coefficient of the x term, by 2 to get -\frac{3}{2}. Then add the square of -\frac{3}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-3x+\frac{9}{4}=-2+\frac{9}{4}
Square -\frac{3}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-3x+\frac{9}{4}=\frac{1}{4}
Add -2 to \frac{9}{4}.
\left(x-\frac{3}{2}\right)^{2}=\frac{1}{4}
Factor x^{2}-3x+\frac{9}{4}. 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}{2}\right)^{2}}=\sqrt{\frac{1}{4}}
Take the square root of both sides of the equation.
x-\frac{3}{2}=\frac{1}{2} x-\frac{3}{2}=-\frac{1}{2}
Simplify.
x=2 x=1
Add \frac{3}{2} to both sides of the equation.