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\frac{1}{2}x-3-\frac{1}{4}x^{2}=-x-3
Subtract \frac{1}{4}x^{2} from both sides.
\frac{1}{2}x-3-\frac{1}{4}x^{2}+x=-3
Add x to both sides.
\frac{3}{2}x-3-\frac{1}{4}x^{2}=-3
Combine \frac{1}{2}x and x to get \frac{3}{2}x.
\frac{3}{2}x-3-\frac{1}{4}x^{2}+3=0
Add 3 to both sides.
\frac{3}{2}x-\frac{1}{4}x^{2}=0
Add -3 and 3 to get 0.
x\left(\frac{3}{2}-\frac{1}{4}x\right)=0
Factor out x.
x=0 x=6
To find equation solutions, solve x=0 and \frac{3}{2}-\frac{x}{4}=0.
\frac{1}{2}x-3-\frac{1}{4}x^{2}=-x-3
Subtract \frac{1}{4}x^{2} from both sides.
\frac{1}{2}x-3-\frac{1}{4}x^{2}+x=-3
Add x to both sides.
\frac{3}{2}x-3-\frac{1}{4}x^{2}=-3
Combine \frac{1}{2}x and x to get \frac{3}{2}x.
\frac{3}{2}x-3-\frac{1}{4}x^{2}+3=0
Add 3 to both sides.
\frac{3}{2}x-\frac{1}{4}x^{2}=0
Add -3 and 3 to get 0.
-\frac{1}{4}x^{2}+\frac{3}{2}x=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{-\frac{3}{2}±\sqrt{\left(\frac{3}{2}\right)^{2}}}{2\left(-\frac{1}{4}\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -\frac{1}{4} for a, \frac{3}{2} for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\frac{3}{2}±\frac{3}{2}}{2\left(-\frac{1}{4}\right)}
Take the square root of \left(\frac{3}{2}\right)^{2}.
x=\frac{-\frac{3}{2}±\frac{3}{2}}{-\frac{1}{2}}
Multiply 2 times -\frac{1}{4}.
x=\frac{0}{-\frac{1}{2}}
Now solve the equation x=\frac{-\frac{3}{2}±\frac{3}{2}}{-\frac{1}{2}} when ± is plus. Add -\frac{3}{2} to \frac{3}{2} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
x=0
Divide 0 by -\frac{1}{2} by multiplying 0 by the reciprocal of -\frac{1}{2}.
x=-\frac{3}{-\frac{1}{2}}
Now solve the equation x=\frac{-\frac{3}{2}±\frac{3}{2}}{-\frac{1}{2}} when ± is minus. Subtract \frac{3}{2} from -\frac{3}{2} by finding a common denominator and subtracting the numerators. Then reduce the fraction to lowest terms if possible.
x=6
Divide -3 by -\frac{1}{2} by multiplying -3 by the reciprocal of -\frac{1}{2}.
x=0 x=6
The equation is now solved.
\frac{1}{2}x-3-\frac{1}{4}x^{2}=-x-3
Subtract \frac{1}{4}x^{2} from both sides.
\frac{1}{2}x-3-\frac{1}{4}x^{2}+x=-3
Add x to both sides.
\frac{3}{2}x-3-\frac{1}{4}x^{2}=-3
Combine \frac{1}{2}x and x to get \frac{3}{2}x.
\frac{3}{2}x-\frac{1}{4}x^{2}=-3+3
Add 3 to both sides.
\frac{3}{2}x-\frac{1}{4}x^{2}=0
Add -3 and 3 to get 0.
-\frac{1}{4}x^{2}+\frac{3}{2}x=0
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{-\frac{1}{4}x^{2}+\frac{3}{2}x}{-\frac{1}{4}}=\frac{0}{-\frac{1}{4}}
Multiply both sides by -4.
x^{2}+\frac{\frac{3}{2}}{-\frac{1}{4}}x=\frac{0}{-\frac{1}{4}}
Dividing by -\frac{1}{4} undoes the multiplication by -\frac{1}{4}.
x^{2}-6x=\frac{0}{-\frac{1}{4}}
Divide \frac{3}{2} by -\frac{1}{4} by multiplying \frac{3}{2} by the reciprocal of -\frac{1}{4}.
x^{2}-6x=0
Divide 0 by -\frac{1}{4} by multiplying 0 by the reciprocal of -\frac{1}{4}.
x^{2}-6x+\left(-3\right)^{2}=\left(-3\right)^{2}
Divide -6, the coefficient of the x term, by 2 to get -3. Then add the square of -3 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-6x+9=9
Square -3.
\left(x-3\right)^{2}=9
Factor x^{2}-6x+9. 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-3\right)^{2}}=\sqrt{9}
Take the square root of both sides of the equation.
x-3=3 x-3=-3
Simplify.
x=6 x=0
Add 3 to both sides of the equation.