Solve for x
x = -\frac{8}{3} = -2\frac{2}{3} \approx -2.666666667
x=3
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x=\frac{8\times 3}{3x}+\frac{x}{3x}
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of x and 3 is 3x. Multiply \frac{8}{x} times \frac{3}{3}. Multiply \frac{1}{3} times \frac{x}{x}.
x=\frac{8\times 3+x}{3x}
Since \frac{8\times 3}{3x} and \frac{x}{3x} have the same denominator, add them by adding their numerators.
x=\frac{24+x}{3x}
Do the multiplications in 8\times 3+x.
x-\frac{24+x}{3x}=0
Subtract \frac{24+x}{3x} from both sides.
\frac{x\times 3x}{3x}-\frac{24+x}{3x}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply x times \frac{3x}{3x}.
\frac{x\times 3x-\left(24+x\right)}{3x}=0
Since \frac{x\times 3x}{3x} and \frac{24+x}{3x} have the same denominator, subtract them by subtracting their numerators.
\frac{3x^{2}-24-x}{3x}=0
Do the multiplications in x\times 3x-\left(24+x\right).
3x^{2}-24-x=0
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 3x.
3x^{2}-x-24=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\left(-24\right)=-72
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 3x^{2}+ax+bx-24. To find a and b, set up a system to be solved.
1,-72 2,-36 3,-24 4,-18 6,-12 8,-9
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product -72.
1-72=-71 2-36=-34 3-24=-21 4-18=-14 6-12=-6 8-9=-1
Calculate the sum for each pair.
a=-9 b=8
The solution is the pair that gives sum -1.
\left(3x^{2}-9x\right)+\left(8x-24\right)
Rewrite 3x^{2}-x-24 as \left(3x^{2}-9x\right)+\left(8x-24\right).
3x\left(x-3\right)+8\left(x-3\right)
Factor out 3x in the first and 8 in the second group.
\left(x-3\right)\left(3x+8\right)
Factor out common term x-3 by using distributive property.
x=3 x=-\frac{8}{3}
To find equation solutions, solve x-3=0 and 3x+8=0.
x=\frac{8\times 3}{3x}+\frac{x}{3x}
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of x and 3 is 3x. Multiply \frac{8}{x} times \frac{3}{3}. Multiply \frac{1}{3} times \frac{x}{x}.
x=\frac{8\times 3+x}{3x}
Since \frac{8\times 3}{3x} and \frac{x}{3x} have the same denominator, add them by adding their numerators.
x=\frac{24+x}{3x}
Do the multiplications in 8\times 3+x.
x-\frac{24+x}{3x}=0
Subtract \frac{24+x}{3x} from both sides.
\frac{x\times 3x}{3x}-\frac{24+x}{3x}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply x times \frac{3x}{3x}.
\frac{x\times 3x-\left(24+x\right)}{3x}=0
Since \frac{x\times 3x}{3x} and \frac{24+x}{3x} have the same denominator, subtract them by subtracting their numerators.
\frac{3x^{2}-24-x}{3x}=0
Do the multiplications in x\times 3x-\left(24+x\right).
3x^{2}-24-x=0
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 3x.
3x^{2}-x-24=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(-1\right)±\sqrt{1-4\times 3\left(-24\right)}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, -1 for b, and -24 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-1\right)±\sqrt{1-12\left(-24\right)}}{2\times 3}
Multiply -4 times 3.
x=\frac{-\left(-1\right)±\sqrt{1+288}}{2\times 3}
Multiply -12 times -24.
x=\frac{-\left(-1\right)±\sqrt{289}}{2\times 3}
Add 1 to 288.
x=\frac{-\left(-1\right)±17}{2\times 3}
Take the square root of 289.
x=\frac{1±17}{2\times 3}
The opposite of -1 is 1.
x=\frac{1±17}{6}
Multiply 2 times 3.
x=\frac{18}{6}
Now solve the equation x=\frac{1±17}{6} when ± is plus. Add 1 to 17.
x=3
Divide 18 by 6.
x=-\frac{16}{6}
Now solve the equation x=\frac{1±17}{6} when ± is minus. Subtract 17 from 1.
x=-\frac{8}{3}
Reduce the fraction \frac{-16}{6} to lowest terms by extracting and canceling out 2.
x=3 x=-\frac{8}{3}
The equation is now solved.
x=\frac{8\times 3}{3x}+\frac{x}{3x}
To add or subtract expressions, expand them to make their denominators the same. Least common multiple of x and 3 is 3x. Multiply \frac{8}{x} times \frac{3}{3}. Multiply \frac{1}{3} times \frac{x}{x}.
x=\frac{8\times 3+x}{3x}
Since \frac{8\times 3}{3x} and \frac{x}{3x} have the same denominator, add them by adding their numerators.
x=\frac{24+x}{3x}
Do the multiplications in 8\times 3+x.
x-\frac{24+x}{3x}=0
Subtract \frac{24+x}{3x} from both sides.
\frac{x\times 3x}{3x}-\frac{24+x}{3x}=0
To add or subtract expressions, expand them to make their denominators the same. Multiply x times \frac{3x}{3x}.
\frac{x\times 3x-\left(24+x\right)}{3x}=0
Since \frac{x\times 3x}{3x} and \frac{24+x}{3x} have the same denominator, subtract them by subtracting their numerators.
\frac{3x^{2}-24-x}{3x}=0
Do the multiplications in x\times 3x-\left(24+x\right).
3x^{2}-24-x=0
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 3x.
3x^{2}-x=24
Add 24 to both sides. Anything plus zero gives itself.
\frac{3x^{2}-x}{3}=\frac{24}{3}
Divide both sides by 3.
x^{2}-\frac{1}{3}x=\frac{24}{3}
Dividing by 3 undoes the multiplication by 3.
x^{2}-\frac{1}{3}x=8
Divide 24 by 3.
x^{2}-\frac{1}{3}x+\left(-\frac{1}{6}\right)^{2}=8+\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}=8+\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{289}{36}
Add 8 to \frac{1}{36}.
\left(x-\frac{1}{6}\right)^{2}=\frac{289}{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{289}{36}}
Take the square root of both sides of the equation.
x-\frac{1}{6}=\frac{17}{6} x-\frac{1}{6}=-\frac{17}{6}
Simplify.
x=3 x=-\frac{8}{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}