Solve for x
x = -\frac{4}{3} = -1\frac{1}{3} \approx -1.333333333
x=1
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3x\times 4x+4x-4\times 3=x\left(1+3x\right)
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 4x, the least common multiple of x,4.
12xx+4x-4\times 3=x\left(1+3x\right)
Multiply 3 and 4 to get 12.
12x^{2}+4x-4\times 3=x\left(1+3x\right)
Multiply x and x to get x^{2}.
12x^{2}+4x-12=x\left(1+3x\right)
Multiply -4 and 3 to get -12.
12x^{2}+4x-12=x+3x^{2}
Use the distributive property to multiply x by 1+3x.
12x^{2}+4x-12-x=3x^{2}
Subtract x from both sides.
12x^{2}+3x-12=3x^{2}
Combine 4x and -x to get 3x.
12x^{2}+3x-12-3x^{2}=0
Subtract 3x^{2} from both sides.
9x^{2}+3x-12=0
Combine 12x^{2} and -3x^{2} to get 9x^{2}.
3x^{2}+x-4=0
Divide both sides by 3.
a+b=1 ab=3\left(-4\right)=-12
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as 3x^{2}+ax+bx-4. To find a and b, set up a system to be solved.
-1,12 -2,6 -3,4
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 -12.
-1+12=11 -2+6=4 -3+4=1
Calculate the sum for each pair.
a=-3 b=4
The solution is the pair that gives sum 1.
\left(3x^{2}-3x\right)+\left(4x-4\right)
Rewrite 3x^{2}+x-4 as \left(3x^{2}-3x\right)+\left(4x-4\right).
3x\left(x-1\right)+4\left(x-1\right)
Factor out 3x in the first and 4 in the second group.
\left(x-1\right)\left(3x+4\right)
Factor out common term x-1 by using distributive property.
x=1 x=-\frac{4}{3}
To find equation solutions, solve x-1=0 and 3x+4=0.
3x\times 4x+4x-4\times 3=x\left(1+3x\right)
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 4x, the least common multiple of x,4.
12xx+4x-4\times 3=x\left(1+3x\right)
Multiply 3 and 4 to get 12.
12x^{2}+4x-4\times 3=x\left(1+3x\right)
Multiply x and x to get x^{2}.
12x^{2}+4x-12=x\left(1+3x\right)
Multiply -4 and 3 to get -12.
12x^{2}+4x-12=x+3x^{2}
Use the distributive property to multiply x by 1+3x.
12x^{2}+4x-12-x=3x^{2}
Subtract x from both sides.
12x^{2}+3x-12=3x^{2}
Combine 4x and -x to get 3x.
12x^{2}+3x-12-3x^{2}=0
Subtract 3x^{2} from both sides.
9x^{2}+3x-12=0
Combine 12x^{2} and -3x^{2} to get 9x^{2}.
x=\frac{-3±\sqrt{3^{2}-4\times 9\left(-12\right)}}{2\times 9}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 9 for a, 3 for b, and -12 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-3±\sqrt{9-4\times 9\left(-12\right)}}{2\times 9}
Square 3.
x=\frac{-3±\sqrt{9-36\left(-12\right)}}{2\times 9}
Multiply -4 times 9.
x=\frac{-3±\sqrt{9+432}}{2\times 9}
Multiply -36 times -12.
x=\frac{-3±\sqrt{441}}{2\times 9}
Add 9 to 432.
x=\frac{-3±21}{2\times 9}
Take the square root of 441.
x=\frac{-3±21}{18}
Multiply 2 times 9.
x=\frac{18}{18}
Now solve the equation x=\frac{-3±21}{18} when ± is plus. Add -3 to 21.
x=1
Divide 18 by 18.
x=-\frac{24}{18}
Now solve the equation x=\frac{-3±21}{18} when ± is minus. Subtract 21 from -3.
x=-\frac{4}{3}
Reduce the fraction \frac{-24}{18} to lowest terms by extracting and canceling out 6.
x=1 x=-\frac{4}{3}
The equation is now solved.
3x\times 4x+4x-4\times 3=x\left(1+3x\right)
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 4x, the least common multiple of x,4.
12xx+4x-4\times 3=x\left(1+3x\right)
Multiply 3 and 4 to get 12.
12x^{2}+4x-4\times 3=x\left(1+3x\right)
Multiply x and x to get x^{2}.
12x^{2}+4x-12=x\left(1+3x\right)
Multiply -4 and 3 to get -12.
12x^{2}+4x-12=x+3x^{2}
Use the distributive property to multiply x by 1+3x.
12x^{2}+4x-12-x=3x^{2}
Subtract x from both sides.
12x^{2}+3x-12=3x^{2}
Combine 4x and -x to get 3x.
12x^{2}+3x-12-3x^{2}=0
Subtract 3x^{2} from both sides.
9x^{2}+3x-12=0
Combine 12x^{2} and -3x^{2} to get 9x^{2}.
9x^{2}+3x=12
Add 12 to both sides. Anything plus zero gives itself.
\frac{9x^{2}+3x}{9}=\frac{12}{9}
Divide both sides by 9.
x^{2}+\frac{3}{9}x=\frac{12}{9}
Dividing by 9 undoes the multiplication by 9.
x^{2}+\frac{1}{3}x=\frac{12}{9}
Reduce the fraction \frac{3}{9} to lowest terms by extracting and canceling out 3.
x^{2}+\frac{1}{3}x=\frac{4}{3}
Reduce the fraction \frac{12}{9} to lowest terms by extracting and canceling out 3.
x^{2}+\frac{1}{3}x+\left(\frac{1}{6}\right)^{2}=\frac{4}{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{4}{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{49}{36}
Add \frac{4}{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{49}{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{49}{36}}
Take the square root of both sides of the equation.
x+\frac{1}{6}=\frac{7}{6} x+\frac{1}{6}=-\frac{7}{6}
Simplify.
x=1 x=-\frac{4}{3}
Subtract \frac{1}{6} from both sides of the equation.
Examples
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{ 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
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Limits
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