Solve for x
x=4
x = \frac{3}{2} = 1\frac{1}{2} = 1.5
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x+\left(x-3\right)\times 4-x\left(-3+x\right)\times 2=0
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 x\left(x-3\right)^{2}, the least common multiple of \left(x-3\right)^{2},x\left(x-3\right),3-x.
x+4x-12-x\left(-3+x\right)\times 2=0
Use the distributive property to multiply x-3 by 4.
5x-12-x\left(-3+x\right)\times 2=0
Combine x and 4x to get 5x.
5x-12-2x\left(-3+x\right)=0
Multiply -1 and 2 to get -2.
5x-12+6x-2x^{2}=0
Use the distributive property to multiply -2x by -3+x.
11x-12-2x^{2}=0
Combine 5x and 6x to get 11x.
-2x^{2}+11x-12=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=11 ab=-2\left(-12\right)=24
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -2x^{2}+ax+bx-12. To find a and b, set up a system to be solved.
1,24 2,12 3,8 4,6
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 24.
1+24=25 2+12=14 3+8=11 4+6=10
Calculate the sum for each pair.
a=8 b=3
The solution is the pair that gives sum 11.
\left(-2x^{2}+8x\right)+\left(3x-12\right)
Rewrite -2x^{2}+11x-12 as \left(-2x^{2}+8x\right)+\left(3x-12\right).
2x\left(-x+4\right)-3\left(-x+4\right)
Factor out 2x in the first and -3 in the second group.
\left(-x+4\right)\left(2x-3\right)
Factor out common term -x+4 by using distributive property.
x=4 x=\frac{3}{2}
To find equation solutions, solve -x+4=0 and 2x-3=0.
x+\left(x-3\right)\times 4-x\left(-3+x\right)\times 2=0
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 x\left(x-3\right)^{2}, the least common multiple of \left(x-3\right)^{2},x\left(x-3\right),3-x.
x+4x-12-x\left(-3+x\right)\times 2=0
Use the distributive property to multiply x-3 by 4.
5x-12-x\left(-3+x\right)\times 2=0
Combine x and 4x to get 5x.
5x-12-2x\left(-3+x\right)=0
Multiply -1 and 2 to get -2.
5x-12+6x-2x^{2}=0
Use the distributive property to multiply -2x by -3+x.
11x-12-2x^{2}=0
Combine 5x and 6x to get 11x.
-2x^{2}+11x-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{-11±\sqrt{11^{2}-4\left(-2\right)\left(-12\right)}}{2\left(-2\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -2 for a, 11 for b, and -12 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-11±\sqrt{121-4\left(-2\right)\left(-12\right)}}{2\left(-2\right)}
Square 11.
x=\frac{-11±\sqrt{121+8\left(-12\right)}}{2\left(-2\right)}
Multiply -4 times -2.
x=\frac{-11±\sqrt{121-96}}{2\left(-2\right)}
Multiply 8 times -12.
x=\frac{-11±\sqrt{25}}{2\left(-2\right)}
Add 121 to -96.
x=\frac{-11±5}{2\left(-2\right)}
Take the square root of 25.
x=\frac{-11±5}{-4}
Multiply 2 times -2.
x=-\frac{6}{-4}
Now solve the equation x=\frac{-11±5}{-4} when ± is plus. Add -11 to 5.
x=\frac{3}{2}
Reduce the fraction \frac{-6}{-4} to lowest terms by extracting and canceling out 2.
x=-\frac{16}{-4}
Now solve the equation x=\frac{-11±5}{-4} when ± is minus. Subtract 5 from -11.
x=4
Divide -16 by -4.
x=\frac{3}{2} x=4
The equation is now solved.
x+\left(x-3\right)\times 4-x\left(-3+x\right)\times 2=0
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 x\left(x-3\right)^{2}, the least common multiple of \left(x-3\right)^{2},x\left(x-3\right),3-x.
x+4x-12-x\left(-3+x\right)\times 2=0
Use the distributive property to multiply x-3 by 4.
5x-12-x\left(-3+x\right)\times 2=0
Combine x and 4x to get 5x.
5x-12-2x\left(-3+x\right)=0
Multiply -1 and 2 to get -2.
5x-12+6x-2x^{2}=0
Use the distributive property to multiply -2x by -3+x.
11x-12-2x^{2}=0
Combine 5x and 6x to get 11x.
11x-2x^{2}=12
Add 12 to both sides. Anything plus zero gives itself.
-2x^{2}+11x=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.
\frac{-2x^{2}+11x}{-2}=\frac{12}{-2}
Divide both sides by -2.
x^{2}+\frac{11}{-2}x=\frac{12}{-2}
Dividing by -2 undoes the multiplication by -2.
x^{2}-\frac{11}{2}x=\frac{12}{-2}
Divide 11 by -2.
x^{2}-\frac{11}{2}x=-6
Divide 12 by -2.
x^{2}-\frac{11}{2}x+\left(-\frac{11}{4}\right)^{2}=-6+\left(-\frac{11}{4}\right)^{2}
Divide -\frac{11}{2}, the coefficient of the x term, by 2 to get -\frac{11}{4}. Then add the square of -\frac{11}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{11}{2}x+\frac{121}{16}=-6+\frac{121}{16}
Square -\frac{11}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{11}{2}x+\frac{121}{16}=\frac{25}{16}
Add -6 to \frac{121}{16}.
\left(x-\frac{11}{4}\right)^{2}=\frac{25}{16}
Factor x^{2}-\frac{11}{2}x+\frac{121}{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{11}{4}\right)^{2}}=\sqrt{\frac{25}{16}}
Take the square root of both sides of the equation.
x-\frac{11}{4}=\frac{5}{4} x-\frac{11}{4}=-\frac{5}{4}
Simplify.
x=4 x=\frac{3}{2}
Add \frac{11}{4} to both sides of the equation.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}