Solve for x
x=4
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-2x\times 2+2x\left(x-3\right)\times \frac{1}{2}=-2\times 6
Variable x cannot be equal to any of the values 0,3 since division by zero is not defined. Multiply both sides of the equation by 2x\left(x-3\right), the least common multiple of 3-x,2,x\left(3-x\right).
-4x+2x\left(x-3\right)\times \frac{1}{2}=-2\times 6
Multiply -2 and 2 to get -4.
-4x+x\left(x-3\right)=-2\times 6
Multiply 2 and \frac{1}{2} to get 1.
-4x+x^{2}-3x=-2\times 6
Use the distributive property to multiply x by x-3.
-7x+x^{2}=-2\times 6
Combine -4x and -3x to get -7x.
-7x+x^{2}=-12
Multiply -2 and 6 to get -12.
-7x+x^{2}+12=0
Add 12 to both sides.
x^{2}-7x+12=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{-\left(-7\right)±\sqrt{\left(-7\right)^{2}-4\times 12}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -7 for b, and 12 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-7\right)±\sqrt{49-4\times 12}}{2}
Square -7.
x=\frac{-\left(-7\right)±\sqrt{49-48}}{2}
Multiply -4 times 12.
x=\frac{-\left(-7\right)±\sqrt{1}}{2}
Add 49 to -48.
x=\frac{-\left(-7\right)±1}{2}
Take the square root of 1.
x=\frac{7±1}{2}
The opposite of -7 is 7.
x=\frac{8}{2}
Now solve the equation x=\frac{7±1}{2} when ± is plus. Add 7 to 1.
x=4
Divide 8 by 2.
x=\frac{6}{2}
Now solve the equation x=\frac{7±1}{2} when ± is minus. Subtract 1 from 7.
x=3
Divide 6 by 2.
x=4 x=3
The equation is now solved.
x=4
Variable x cannot be equal to 3.
-2x\times 2+2x\left(x-3\right)\times \frac{1}{2}=-2\times 6
Variable x cannot be equal to any of the values 0,3 since division by zero is not defined. Multiply both sides of the equation by 2x\left(x-3\right), the least common multiple of 3-x,2,x\left(3-x\right).
-4x+2x\left(x-3\right)\times \frac{1}{2}=-2\times 6
Multiply -2 and 2 to get -4.
-4x+x\left(x-3\right)=-2\times 6
Multiply 2 and \frac{1}{2} to get 1.
-4x+x^{2}-3x=-2\times 6
Use the distributive property to multiply x by x-3.
-7x+x^{2}=-2\times 6
Combine -4x and -3x to get -7x.
-7x+x^{2}=-12
Multiply -2 and 6 to get -12.
x^{2}-7x=-12
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.
x^{2}-7x+\left(-\frac{7}{2}\right)^{2}=-12+\left(-\frac{7}{2}\right)^{2}
Divide -7, the coefficient of the x term, by 2 to get -\frac{7}{2}. Then add the square of -\frac{7}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-7x+\frac{49}{4}=-12+\frac{49}{4}
Square -\frac{7}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-7x+\frac{49}{4}=\frac{1}{4}
Add -12 to \frac{49}{4}.
\left(x-\frac{7}{2}\right)^{2}=\frac{1}{4}
Factor x^{2}-7x+\frac{49}{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{7}{2}\right)^{2}}=\sqrt{\frac{1}{4}}
Take the square root of both sides of the equation.
x-\frac{7}{2}=\frac{1}{2} x-\frac{7}{2}=-\frac{1}{2}
Simplify.
x=4 x=3
Add \frac{7}{2} to both sides of the equation.
x=4
Variable x cannot be equal to 3.
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