Solve for x
x=1
x=2
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Polynomial
5 problems similar to:
x - \frac { 2 x + 3 } { 3 } = \frac { 3 x ^ { 2 } - 7 x } { 6 }
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6x-2\left(2x+3\right)=3x^{2}-7x
Multiply both sides of the equation by 6, the least common multiple of 3,6.
6x-4x-6=3x^{2}-7x
Use the distributive property to multiply -2 by 2x+3.
2x-6=3x^{2}-7x
Combine 6x and -4x to get 2x.
2x-6-3x^{2}=-7x
Subtract 3x^{2} from both sides.
2x-6-3x^{2}+7x=0
Add 7x to both sides.
9x-6-3x^{2}=0
Combine 2x and 7x to get 9x.
3x-2-x^{2}=0
Divide both sides by 3.
-x^{2}+3x-2=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=3 ab=-\left(-2\right)=2
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -x^{2}+ax+bx-2. To find a and b, set up a system to be solved.
a=2 b=1
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. The only such pair is the system solution.
\left(-x^{2}+2x\right)+\left(x-2\right)
Rewrite -x^{2}+3x-2 as \left(-x^{2}+2x\right)+\left(x-2\right).
-x\left(x-2\right)+x-2
Factor out -x in -x^{2}+2x.
\left(x-2\right)\left(-x+1\right)
Factor out common term x-2 by using distributive property.
x=2 x=1
To find equation solutions, solve x-2=0 and -x+1=0.
6x-2\left(2x+3\right)=3x^{2}-7x
Multiply both sides of the equation by 6, the least common multiple of 3,6.
6x-4x-6=3x^{2}-7x
Use the distributive property to multiply -2 by 2x+3.
2x-6=3x^{2}-7x
Combine 6x and -4x to get 2x.
2x-6-3x^{2}=-7x
Subtract 3x^{2} from both sides.
2x-6-3x^{2}+7x=0
Add 7x to both sides.
9x-6-3x^{2}=0
Combine 2x and 7x to get 9x.
-3x^{2}+9x-6=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{-9±\sqrt{9^{2}-4\left(-3\right)\left(-6\right)}}{2\left(-3\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -3 for a, 9 for b, and -6 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-9±\sqrt{81-4\left(-3\right)\left(-6\right)}}{2\left(-3\right)}
Square 9.
x=\frac{-9±\sqrt{81+12\left(-6\right)}}{2\left(-3\right)}
Multiply -4 times -3.
x=\frac{-9±\sqrt{81-72}}{2\left(-3\right)}
Multiply 12 times -6.
x=\frac{-9±\sqrt{9}}{2\left(-3\right)}
Add 81 to -72.
x=\frac{-9±3}{2\left(-3\right)}
Take the square root of 9.
x=\frac{-9±3}{-6}
Multiply 2 times -3.
x=-\frac{6}{-6}
Now solve the equation x=\frac{-9±3}{-6} when ± is plus. Add -9 to 3.
x=1
Divide -6 by -6.
x=-\frac{12}{-6}
Now solve the equation x=\frac{-9±3}{-6} when ± is minus. Subtract 3 from -9.
x=2
Divide -12 by -6.
x=1 x=2
The equation is now solved.
6x-2\left(2x+3\right)=3x^{2}-7x
Multiply both sides of the equation by 6, the least common multiple of 3,6.
6x-4x-6=3x^{2}-7x
Use the distributive property to multiply -2 by 2x+3.
2x-6=3x^{2}-7x
Combine 6x and -4x to get 2x.
2x-6-3x^{2}=-7x
Subtract 3x^{2} from both sides.
2x-6-3x^{2}+7x=0
Add 7x to both sides.
9x-6-3x^{2}=0
Combine 2x and 7x to get 9x.
9x-3x^{2}=6
Add 6 to both sides. Anything plus zero gives itself.
-3x^{2}+9x=6
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}+9x}{-3}=\frac{6}{-3}
Divide both sides by -3.
x^{2}+\frac{9}{-3}x=\frac{6}{-3}
Dividing by -3 undoes the multiplication by -3.
x^{2}-3x=\frac{6}{-3}
Divide 9 by -3.
x^{2}-3x=-2
Divide 6 by -3.
x^{2}-3x+\left(-\frac{3}{2}\right)^{2}=-2+\left(-\frac{3}{2}\right)^{2}
Divide -3, the coefficient of the x term, by 2 to get -\frac{3}{2}. Then add the square of -\frac{3}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-3x+\frac{9}{4}=-2+\frac{9}{4}
Square -\frac{3}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-3x+\frac{9}{4}=\frac{1}{4}
Add -2 to \frac{9}{4}.
\left(x-\frac{3}{2}\right)^{2}=\frac{1}{4}
Factor x^{2}-3x+\frac{9}{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{3}{2}\right)^{2}}=\sqrt{\frac{1}{4}}
Take the square root of both sides of the equation.
x-\frac{3}{2}=\frac{1}{2} x-\frac{3}{2}=-\frac{1}{2}
Simplify.
x=2 x=1
Add \frac{3}{2} 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}