Solve for x
x=-\frac{1}{6}\approx -0.166666667
x=1
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3\left(x+1\right)+2\left(x-1\right)=6x^{2}
Multiply both sides of the equation by 6, the least common multiple of 2,3.
3x+3+2\left(x-1\right)=6x^{2}
Use the distributive property to multiply 3 by x+1.
3x+3+2x-2=6x^{2}
Use the distributive property to multiply 2 by x-1.
5x+3-2=6x^{2}
Combine 3x and 2x to get 5x.
5x+1=6x^{2}
Subtract 2 from 3 to get 1.
5x+1-6x^{2}=0
Subtract 6x^{2} from both sides.
-6x^{2}+5x+1=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=5 ab=-6=-6
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -6x^{2}+ax+bx+1. 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=6 b=-1
The solution is the pair that gives sum 5.
\left(-6x^{2}+6x\right)+\left(-x+1\right)
Rewrite -6x^{2}+5x+1 as \left(-6x^{2}+6x\right)+\left(-x+1\right).
6x\left(-x+1\right)-x+1
Factor out 6x in -6x^{2}+6x.
\left(-x+1\right)\left(6x+1\right)
Factor out common term -x+1 by using distributive property.
x=1 x=-\frac{1}{6}
To find equation solutions, solve -x+1=0 and 6x+1=0.
3\left(x+1\right)+2\left(x-1\right)=6x^{2}
Multiply both sides of the equation by 6, the least common multiple of 2,3.
3x+3+2\left(x-1\right)=6x^{2}
Use the distributive property to multiply 3 by x+1.
3x+3+2x-2=6x^{2}
Use the distributive property to multiply 2 by x-1.
5x+3-2=6x^{2}
Combine 3x and 2x to get 5x.
5x+1=6x^{2}
Subtract 2 from 3 to get 1.
5x+1-6x^{2}=0
Subtract 6x^{2} from both sides.
-6x^{2}+5x+1=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{-5±\sqrt{5^{2}-4\left(-6\right)}}{2\left(-6\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -6 for a, 5 for b, and 1 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-5±\sqrt{25-4\left(-6\right)}}{2\left(-6\right)}
Square 5.
x=\frac{-5±\sqrt{25+24}}{2\left(-6\right)}
Multiply -4 times -6.
x=\frac{-5±\sqrt{49}}{2\left(-6\right)}
Add 25 to 24.
x=\frac{-5±7}{2\left(-6\right)}
Take the square root of 49.
x=\frac{-5±7}{-12}
Multiply 2 times -6.
x=\frac{2}{-12}
Now solve the equation x=\frac{-5±7}{-12} when ± is plus. Add -5 to 7.
x=-\frac{1}{6}
Reduce the fraction \frac{2}{-12} to lowest terms by extracting and canceling out 2.
x=-\frac{12}{-12}
Now solve the equation x=\frac{-5±7}{-12} when ± is minus. Subtract 7 from -5.
x=1
Divide -12 by -12.
x=-\frac{1}{6} x=1
The equation is now solved.
3\left(x+1\right)+2\left(x-1\right)=6x^{2}
Multiply both sides of the equation by 6, the least common multiple of 2,3.
3x+3+2\left(x-1\right)=6x^{2}
Use the distributive property to multiply 3 by x+1.
3x+3+2x-2=6x^{2}
Use the distributive property to multiply 2 by x-1.
5x+3-2=6x^{2}
Combine 3x and 2x to get 5x.
5x+1=6x^{2}
Subtract 2 from 3 to get 1.
5x+1-6x^{2}=0
Subtract 6x^{2} from both sides.
5x-6x^{2}=-1
Subtract 1 from both sides. Anything subtracted from zero gives its negation.
-6x^{2}+5x=-1
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{-6x^{2}+5x}{-6}=-\frac{1}{-6}
Divide both sides by -6.
x^{2}+\frac{5}{-6}x=-\frac{1}{-6}
Dividing by -6 undoes the multiplication by -6.
x^{2}-\frac{5}{6}x=-\frac{1}{-6}
Divide 5 by -6.
x^{2}-\frac{5}{6}x=\frac{1}{6}
Divide -1 by -6.
x^{2}-\frac{5}{6}x+\left(-\frac{5}{12}\right)^{2}=\frac{1}{6}+\left(-\frac{5}{12}\right)^{2}
Divide -\frac{5}{6}, the coefficient of the x term, by 2 to get -\frac{5}{12}. Then add the square of -\frac{5}{12} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{5}{6}x+\frac{25}{144}=\frac{1}{6}+\frac{25}{144}
Square -\frac{5}{12} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{5}{6}x+\frac{25}{144}=\frac{49}{144}
Add \frac{1}{6} to \frac{25}{144} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{5}{12}\right)^{2}=\frac{49}{144}
Factor x^{2}-\frac{5}{6}x+\frac{25}{144}. 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{5}{12}\right)^{2}}=\sqrt{\frac{49}{144}}
Take the square root of both sides of the equation.
x-\frac{5}{12}=\frac{7}{12} x-\frac{5}{12}=-\frac{7}{12}
Simplify.
x=1 x=-\frac{1}{6}
Add \frac{5}{12} 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}