Solve for x
x=2
x = \frac{13}{9} = 1\frac{4}{9} \approx 1.444444444
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7x-10-1=3\left(x-1\right)\left(3x-5\right)
Combine 6x and x to get 7x.
7x-11=3\left(x-1\right)\left(3x-5\right)
Subtract 1 from -10 to get -11.
7x-11=\left(3x-3\right)\left(3x-5\right)
Use the distributive property to multiply 3 by x-1.
7x-11=9x^{2}-24x+15
Use the distributive property to multiply 3x-3 by 3x-5 and combine like terms.
7x-11-9x^{2}=-24x+15
Subtract 9x^{2} from both sides.
7x-11-9x^{2}+24x=15
Add 24x to both sides.
31x-11-9x^{2}=15
Combine 7x and 24x to get 31x.
31x-11-9x^{2}-15=0
Subtract 15 from both sides.
31x-26-9x^{2}=0
Subtract 15 from -11 to get -26.
-9x^{2}+31x-26=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{-31±\sqrt{31^{2}-4\left(-9\right)\left(-26\right)}}{2\left(-9\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -9 for a, 31 for b, and -26 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-31±\sqrt{961-4\left(-9\right)\left(-26\right)}}{2\left(-9\right)}
Square 31.
x=\frac{-31±\sqrt{961+36\left(-26\right)}}{2\left(-9\right)}
Multiply -4 times -9.
x=\frac{-31±\sqrt{961-936}}{2\left(-9\right)}
Multiply 36 times -26.
x=\frac{-31±\sqrt{25}}{2\left(-9\right)}
Add 961 to -936.
x=\frac{-31±5}{2\left(-9\right)}
Take the square root of 25.
x=\frac{-31±5}{-18}
Multiply 2 times -9.
x=-\frac{26}{-18}
Now solve the equation x=\frac{-31±5}{-18} when ± is plus. Add -31 to 5.
x=\frac{13}{9}
Reduce the fraction \frac{-26}{-18} to lowest terms by extracting and canceling out 2.
x=-\frac{36}{-18}
Now solve the equation x=\frac{-31±5}{-18} when ± is minus. Subtract 5 from -31.
x=2
Divide -36 by -18.
x=\frac{13}{9} x=2
The equation is now solved.
7x-10-1=3\left(x-1\right)\left(3x-5\right)
Combine 6x and x to get 7x.
7x-11=3\left(x-1\right)\left(3x-5\right)
Subtract 1 from -10 to get -11.
7x-11=\left(3x-3\right)\left(3x-5\right)
Use the distributive property to multiply 3 by x-1.
7x-11=9x^{2}-24x+15
Use the distributive property to multiply 3x-3 by 3x-5 and combine like terms.
7x-11-9x^{2}=-24x+15
Subtract 9x^{2} from both sides.
7x-11-9x^{2}+24x=15
Add 24x to both sides.
31x-11-9x^{2}=15
Combine 7x and 24x to get 31x.
31x-9x^{2}=15+11
Add 11 to both sides.
31x-9x^{2}=26
Add 15 and 11 to get 26.
-9x^{2}+31x=26
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{-9x^{2}+31x}{-9}=\frac{26}{-9}
Divide both sides by -9.
x^{2}+\frac{31}{-9}x=\frac{26}{-9}
Dividing by -9 undoes the multiplication by -9.
x^{2}-\frac{31}{9}x=\frac{26}{-9}
Divide 31 by -9.
x^{2}-\frac{31}{9}x=-\frac{26}{9}
Divide 26 by -9.
x^{2}-\frac{31}{9}x+\left(-\frac{31}{18}\right)^{2}=-\frac{26}{9}+\left(-\frac{31}{18}\right)^{2}
Divide -\frac{31}{9}, the coefficient of the x term, by 2 to get -\frac{31}{18}. Then add the square of -\frac{31}{18} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{31}{9}x+\frac{961}{324}=-\frac{26}{9}+\frac{961}{324}
Square -\frac{31}{18} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{31}{9}x+\frac{961}{324}=\frac{25}{324}
Add -\frac{26}{9} to \frac{961}{324} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{31}{18}\right)^{2}=\frac{25}{324}
Factor x^{2}-\frac{31}{9}x+\frac{961}{324}. 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{31}{18}\right)^{2}}=\sqrt{\frac{25}{324}}
Take the square root of both sides of the equation.
x-\frac{31}{18}=\frac{5}{18} x-\frac{31}{18}=-\frac{5}{18}
Simplify.
x=2 x=\frac{13}{9}
Add \frac{31}{18} 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}