Solve for x
x=-\frac{2}{3}\approx -0.666666667
x=1
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\left(x+1\right)\times 2+x\times 2=3x\left(x+1\right)
Variable x cannot be equal to any of the values -1,0 since division by zero is not defined. Multiply both sides of the equation by x\left(x+1\right), the least common multiple of x,x+1.
2x+2+x\times 2=3x\left(x+1\right)
Use the distributive property to multiply x+1 by 2.
4x+2=3x\left(x+1\right)
Combine 2x and x\times 2 to get 4x.
4x+2=3x^{2}+3x
Use the distributive property to multiply 3x by x+1.
4x+2-3x^{2}=3x
Subtract 3x^{2} from both sides.
4x+2-3x^{2}-3x=0
Subtract 3x from both sides.
x+2-3x^{2}=0
Combine 4x and -3x to get x.
-3x^{2}+x+2=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=1 ab=-3\times 2=-6
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -3x^{2}+ax+bx+2. To find a and b, set up a system to be solved.
-1,6 -2,3
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 -6.
-1+6=5 -2+3=1
Calculate the sum for each pair.
a=3 b=-2
The solution is the pair that gives sum 1.
\left(-3x^{2}+3x\right)+\left(-2x+2\right)
Rewrite -3x^{2}+x+2 as \left(-3x^{2}+3x\right)+\left(-2x+2\right).
3x\left(-x+1\right)+2\left(-x+1\right)
Factor out 3x in the first and 2 in the second group.
\left(-x+1\right)\left(3x+2\right)
Factor out common term -x+1 by using distributive property.
x=1 x=-\frac{2}{3}
To find equation solutions, solve -x+1=0 and 3x+2=0.
\left(x+1\right)\times 2+x\times 2=3x\left(x+1\right)
Variable x cannot be equal to any of the values -1,0 since division by zero is not defined. Multiply both sides of the equation by x\left(x+1\right), the least common multiple of x,x+1.
2x+2+x\times 2=3x\left(x+1\right)
Use the distributive property to multiply x+1 by 2.
4x+2=3x\left(x+1\right)
Combine 2x and x\times 2 to get 4x.
4x+2=3x^{2}+3x
Use the distributive property to multiply 3x by x+1.
4x+2-3x^{2}=3x
Subtract 3x^{2} from both sides.
4x+2-3x^{2}-3x=0
Subtract 3x from both sides.
x+2-3x^{2}=0
Combine 4x and -3x to get x.
-3x^{2}+x+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{-1±\sqrt{1^{2}-4\left(-3\right)\times 2}}{2\left(-3\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -3 for a, 1 for b, and 2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-1±\sqrt{1-4\left(-3\right)\times 2}}{2\left(-3\right)}
Square 1.
x=\frac{-1±\sqrt{1+12\times 2}}{2\left(-3\right)}
Multiply -4 times -3.
x=\frac{-1±\sqrt{1+24}}{2\left(-3\right)}
Multiply 12 times 2.
x=\frac{-1±\sqrt{25}}{2\left(-3\right)}
Add 1 to 24.
x=\frac{-1±5}{2\left(-3\right)}
Take the square root of 25.
x=\frac{-1±5}{-6}
Multiply 2 times -3.
x=\frac{4}{-6}
Now solve the equation x=\frac{-1±5}{-6} when ± is plus. Add -1 to 5.
x=-\frac{2}{3}
Reduce the fraction \frac{4}{-6} to lowest terms by extracting and canceling out 2.
x=-\frac{6}{-6}
Now solve the equation x=\frac{-1±5}{-6} when ± is minus. Subtract 5 from -1.
x=1
Divide -6 by -6.
x=-\frac{2}{3} x=1
The equation is now solved.
\left(x+1\right)\times 2+x\times 2=3x\left(x+1\right)
Variable x cannot be equal to any of the values -1,0 since division by zero is not defined. Multiply both sides of the equation by x\left(x+1\right), the least common multiple of x,x+1.
2x+2+x\times 2=3x\left(x+1\right)
Use the distributive property to multiply x+1 by 2.
4x+2=3x\left(x+1\right)
Combine 2x and x\times 2 to get 4x.
4x+2=3x^{2}+3x
Use the distributive property to multiply 3x by x+1.
4x+2-3x^{2}=3x
Subtract 3x^{2} from both sides.
4x+2-3x^{2}-3x=0
Subtract 3x from both sides.
x+2-3x^{2}=0
Combine 4x and -3x to get x.
x-3x^{2}=-2
Subtract 2 from both sides. Anything subtracted from zero gives its negation.
-3x^{2}+x=-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{-3x^{2}+x}{-3}=-\frac{2}{-3}
Divide both sides by -3.
x^{2}+\frac{1}{-3}x=-\frac{2}{-3}
Dividing by -3 undoes the multiplication by -3.
x^{2}-\frac{1}{3}x=-\frac{2}{-3}
Divide 1 by -3.
x^{2}-\frac{1}{3}x=\frac{2}{3}
Divide -2 by -3.
x^{2}-\frac{1}{3}x+\left(-\frac{1}{6}\right)^{2}=\frac{2}{3}+\left(-\frac{1}{6}\right)^{2}
Divide -\frac{1}{3}, the coefficient of the x term, by 2 to get -\frac{1}{6}. Then add the square of -\frac{1}{6} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{1}{3}x+\frac{1}{36}=\frac{2}{3}+\frac{1}{36}
Square -\frac{1}{6} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{1}{3}x+\frac{1}{36}=\frac{25}{36}
Add \frac{2}{3} to \frac{1}{36} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{1}{6}\right)^{2}=\frac{25}{36}
Factor x^{2}-\frac{1}{3}x+\frac{1}{36}. 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}{6}\right)^{2}}=\sqrt{\frac{25}{36}}
Take the square root of both sides of the equation.
x-\frac{1}{6}=\frac{5}{6} x-\frac{1}{6}=-\frac{5}{6}
Simplify.
x=1 x=-\frac{2}{3}
Add \frac{1}{6} 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}