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2x^{2}=6-x
Variable x cannot be equal to 3 since division by zero is not defined. Multiply both sides of the equation by x-3.
2x^{2}-6=-x
Subtract 6 from both sides.
2x^{2}-6+x=0
Add x to both sides.
2x^{2}+x-6=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\left(-6\right)=-12
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 2x^{2}+ax+bx-6. To find a and b, set up a system to be solved.
-1,12 -2,6 -3,4
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 -12.
-1+12=11 -2+6=4 -3+4=1
Calculate the sum for each pair.
a=-3 b=4
The solution is the pair that gives sum 1.
\left(2x^{2}-3x\right)+\left(4x-6\right)
Rewrite 2x^{2}+x-6 as \left(2x^{2}-3x\right)+\left(4x-6\right).
x\left(2x-3\right)+2\left(2x-3\right)
Factor out x in the first and 2 in the second group.
\left(2x-3\right)\left(x+2\right)
Factor out common term 2x-3 by using distributive property.
x=\frac{3}{2} x=-2
To find equation solutions, solve 2x-3=0 and x+2=0.
2x^{2}=6-x
Variable x cannot be equal to 3 since division by zero is not defined. Multiply both sides of the equation by x-3.
2x^{2}-6=-x
Subtract 6 from both sides.
2x^{2}-6+x=0
Add x to both sides.
2x^{2}+x-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{-1±\sqrt{1^{2}-4\times 2\left(-6\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, 1 for b, and -6 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-1±\sqrt{1-4\times 2\left(-6\right)}}{2\times 2}
Square 1.
x=\frac{-1±\sqrt{1-8\left(-6\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{-1±\sqrt{1+48}}{2\times 2}
Multiply -8 times -6.
x=\frac{-1±\sqrt{49}}{2\times 2}
Add 1 to 48.
x=\frac{-1±7}{2\times 2}
Take the square root of 49.
x=\frac{-1±7}{4}
Multiply 2 times 2.
x=\frac{6}{4}
Now solve the equation x=\frac{-1±7}{4} when ± is plus. Add -1 to 7.
x=\frac{3}{2}
Reduce the fraction \frac{6}{4} to lowest terms by extracting and canceling out 2.
x=-\frac{8}{4}
Now solve the equation x=\frac{-1±7}{4} when ± is minus. Subtract 7 from -1.
x=-2
Divide -8 by 4.
x=\frac{3}{2} x=-2
The equation is now solved.
2x^{2}=6-x
Variable x cannot be equal to 3 since division by zero is not defined. Multiply both sides of the equation by x-3.
2x^{2}+x=6
Add x to both sides.
\frac{2x^{2}+x}{2}=\frac{6}{2}
Divide both sides by 2.
x^{2}+\frac{1}{2}x=\frac{6}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}+\frac{1}{2}x=3
Divide 6 by 2.
x^{2}+\frac{1}{2}x+\left(\frac{1}{4}\right)^{2}=3+\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}=3+\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{49}{16}
Add 3 to \frac{1}{16}.
\left(x+\frac{1}{4}\right)^{2}=\frac{49}{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{49}{16}}
Take the square root of both sides of the equation.
x+\frac{1}{4}=\frac{7}{4} x+\frac{1}{4}=-\frac{7}{4}
Simplify.
x=\frac{3}{2} x=-2
Subtract \frac{1}{4} from both sides of the equation.