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2=3x+3x^{2}\left(-\frac{1}{3}\right)
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 3x^{2}, the least common multiple of 3x^{2},x,3.
2=3x-x^{2}
Multiply 3 and -\frac{1}{3} to get -1.
3x-x^{2}=2
Swap sides so that all variable terms are on the left hand side.
3x-x^{2}-2=0
Subtract 2 from both sides.
-x^{2}+3x-2=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=3 ab=-\left(-2\right)=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 positive, a and b are both positive. 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)+x-2
Factor out -x in -x^{2}+2x.
\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.
2=3x+3x^{2}\left(-\frac{1}{3}\right)
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 3x^{2}, the least common multiple of 3x^{2},x,3.
2=3x-x^{2}
Multiply 3 and -\frac{1}{3} to get -1.
3x-x^{2}=2
Swap sides so that all variable terms are on the left hand side.
3x-x^{2}-2=0
Subtract 2 from both sides.
-x^{2}+3x-2=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{-3±\sqrt{3^{2}-4\left(-1\right)\left(-2\right)}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 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(-1\right)\left(-2\right)}}{2\left(-1\right)}
Square 3.
x=\frac{-3±\sqrt{9+4\left(-2\right)}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{-3±\sqrt{9-8}}{2\left(-1\right)}
Multiply 4 times -2.
x=\frac{-3±\sqrt{1}}{2\left(-1\right)}
Add 9 to -8.
x=\frac{-3±1}{2\left(-1\right)}
Take the square root of 1.
x=\frac{-3±1}{-2}
Multiply 2 times -1.
x=-\frac{2}{-2}
Now solve the equation x=\frac{-3±1}{-2} when ± is plus. Add -3 to 1.
x=1
Divide -2 by -2.
x=-\frac{4}{-2}
Now solve the equation x=\frac{-3±1}{-2} when ± is minus. Subtract 1 from -3.
x=2
Divide -4 by -2.
x=1 x=2
The equation is now solved.
2=3x+3x^{2}\left(-\frac{1}{3}\right)
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 3x^{2}, the least common multiple of 3x^{2},x,3.
2=3x-x^{2}
Multiply 3 and -\frac{1}{3} to get -1.
3x-x^{2}=2
Swap sides so that all variable terms are on the left hand side.
-x^{2}+3x=2
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{-x^{2}+3x}{-1}=\frac{2}{-1}
Divide both sides by -1.
x^{2}+\frac{3}{-1}x=\frac{2}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}-3x=\frac{2}{-1}
Divide 3 by -1.
x^{2}-3x=-2
Divide 2 by -1.
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.