Solve for x
x=5
x=-\frac{1}{5}=-0.2
Graph
Share
Copied to clipboard
\left(6x+6\right)\left(x+1\right)-\left(6x-6\right)\left(x-1\right)=5\left(x-1\right)\left(x+1\right)
Variable x cannot be equal to any of the values -1,1 since division by zero is not defined. Multiply both sides of the equation by 6\left(x-1\right)\left(x+1\right), the least common multiple of x-1,x+1,6.
6x^{2}+12x+6-\left(6x-6\right)\left(x-1\right)=5\left(x-1\right)\left(x+1\right)
Use the distributive property to multiply 6x+6 by x+1 and combine like terms.
6x^{2}+12x+6-\left(6x^{2}-12x+6\right)=5\left(x-1\right)\left(x+1\right)
Use the distributive property to multiply 6x-6 by x-1 and combine like terms.
6x^{2}+12x+6-6x^{2}+12x-6=5\left(x-1\right)\left(x+1\right)
To find the opposite of 6x^{2}-12x+6, find the opposite of each term.
12x+6+12x-6=5\left(x-1\right)\left(x+1\right)
Combine 6x^{2} and -6x^{2} to get 0.
24x+6-6=5\left(x-1\right)\left(x+1\right)
Combine 12x and 12x to get 24x.
24x=5\left(x-1\right)\left(x+1\right)
Subtract 6 from 6 to get 0.
24x=\left(5x-5\right)\left(x+1\right)
Use the distributive property to multiply 5 by x-1.
24x=5x^{2}-5
Use the distributive property to multiply 5x-5 by x+1 and combine like terms.
24x-5x^{2}=-5
Subtract 5x^{2} from both sides.
24x-5x^{2}+5=0
Add 5 to both sides.
-5x^{2}+24x+5=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{-24±\sqrt{24^{2}-4\left(-5\right)\times 5}}{2\left(-5\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -5 for a, 24 for b, and 5 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-24±\sqrt{576-4\left(-5\right)\times 5}}{2\left(-5\right)}
Square 24.
x=\frac{-24±\sqrt{576+20\times 5}}{2\left(-5\right)}
Multiply -4 times -5.
x=\frac{-24±\sqrt{576+100}}{2\left(-5\right)}
Multiply 20 times 5.
x=\frac{-24±\sqrt{676}}{2\left(-5\right)}
Add 576 to 100.
x=\frac{-24±26}{2\left(-5\right)}
Take the square root of 676.
x=\frac{-24±26}{-10}
Multiply 2 times -5.
x=\frac{2}{-10}
Now solve the equation x=\frac{-24±26}{-10} when ± is plus. Add -24 to 26.
x=-\frac{1}{5}
Reduce the fraction \frac{2}{-10} to lowest terms by extracting and canceling out 2.
x=-\frac{50}{-10}
Now solve the equation x=\frac{-24±26}{-10} when ± is minus. Subtract 26 from -24.
x=5
Divide -50 by -10.
x=-\frac{1}{5} x=5
The equation is now solved.
\left(6x+6\right)\left(x+1\right)-\left(6x-6\right)\left(x-1\right)=5\left(x-1\right)\left(x+1\right)
Variable x cannot be equal to any of the values -1,1 since division by zero is not defined. Multiply both sides of the equation by 6\left(x-1\right)\left(x+1\right), the least common multiple of x-1,x+1,6.
6x^{2}+12x+6-\left(6x-6\right)\left(x-1\right)=5\left(x-1\right)\left(x+1\right)
Use the distributive property to multiply 6x+6 by x+1 and combine like terms.
6x^{2}+12x+6-\left(6x^{2}-12x+6\right)=5\left(x-1\right)\left(x+1\right)
Use the distributive property to multiply 6x-6 by x-1 and combine like terms.
6x^{2}+12x+6-6x^{2}+12x-6=5\left(x-1\right)\left(x+1\right)
To find the opposite of 6x^{2}-12x+6, find the opposite of each term.
12x+6+12x-6=5\left(x-1\right)\left(x+1\right)
Combine 6x^{2} and -6x^{2} to get 0.
24x+6-6=5\left(x-1\right)\left(x+1\right)
Combine 12x and 12x to get 24x.
24x=5\left(x-1\right)\left(x+1\right)
Subtract 6 from 6 to get 0.
24x=\left(5x-5\right)\left(x+1\right)
Use the distributive property to multiply 5 by x-1.
24x=5x^{2}-5
Use the distributive property to multiply 5x-5 by x+1 and combine like terms.
24x-5x^{2}=-5
Subtract 5x^{2} from both sides.
-5x^{2}+24x=-5
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{-5x^{2}+24x}{-5}=-\frac{5}{-5}
Divide both sides by -5.
x^{2}+\frac{24}{-5}x=-\frac{5}{-5}
Dividing by -5 undoes the multiplication by -5.
x^{2}-\frac{24}{5}x=-\frac{5}{-5}
Divide 24 by -5.
x^{2}-\frac{24}{5}x=1
Divide -5 by -5.
x^{2}-\frac{24}{5}x+\left(-\frac{12}{5}\right)^{2}=1+\left(-\frac{12}{5}\right)^{2}
Divide -\frac{24}{5}, the coefficient of the x term, by 2 to get -\frac{12}{5}. Then add the square of -\frac{12}{5} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{24}{5}x+\frac{144}{25}=1+\frac{144}{25}
Square -\frac{12}{5} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{24}{5}x+\frac{144}{25}=\frac{169}{25}
Add 1 to \frac{144}{25}.
\left(x-\frac{12}{5}\right)^{2}=\frac{169}{25}
Factor x^{2}-\frac{24}{5}x+\frac{144}{25}. 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{12}{5}\right)^{2}}=\sqrt{\frac{169}{25}}
Take the square root of both sides of the equation.
x-\frac{12}{5}=\frac{13}{5} x-\frac{12}{5}=-\frac{13}{5}
Simplify.
x=5 x=-\frac{1}{5}
Add \frac{12}{5} 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}