Solve for x
x = \frac{6}{5} = 1\frac{1}{5} = 1.2
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2=\left(x-3\right)\left(x-1\right)\left(-5\right)+x-1
Variable x cannot be equal to any of the values 1,3 since division by zero is not defined. Multiply both sides of the equation by \left(x-3\right)\left(x-1\right), the least common multiple of \left(x-1\right)\left(x-3\right),x-3.
2=\left(x^{2}-4x+3\right)\left(-5\right)+x-1
Use the distributive property to multiply x-3 by x-1 and combine like terms.
2=-5x^{2}+20x-15+x-1
Use the distributive property to multiply x^{2}-4x+3 by -5.
2=-5x^{2}+21x-15-1
Combine 20x and x to get 21x.
2=-5x^{2}+21x-16
Subtract 1 from -15 to get -16.
-5x^{2}+21x-16=2
Swap sides so that all variable terms are on the left hand side.
-5x^{2}+21x-16-2=0
Subtract 2 from both sides.
-5x^{2}+21x-18=0
Subtract 2 from -16 to get -18.
x=\frac{-21±\sqrt{21^{2}-4\left(-5\right)\left(-18\right)}}{2\left(-5\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -5 for a, 21 for b, and -18 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-21±\sqrt{441-4\left(-5\right)\left(-18\right)}}{2\left(-5\right)}
Square 21.
x=\frac{-21±\sqrt{441+20\left(-18\right)}}{2\left(-5\right)}
Multiply -4 times -5.
x=\frac{-21±\sqrt{441-360}}{2\left(-5\right)}
Multiply 20 times -18.
x=\frac{-21±\sqrt{81}}{2\left(-5\right)}
Add 441 to -360.
x=\frac{-21±9}{2\left(-5\right)}
Take the square root of 81.
x=\frac{-21±9}{-10}
Multiply 2 times -5.
x=-\frac{12}{-10}
Now solve the equation x=\frac{-21±9}{-10} when ± is plus. Add -21 to 9.
x=\frac{6}{5}
Reduce the fraction \frac{-12}{-10} to lowest terms by extracting and canceling out 2.
x=-\frac{30}{-10}
Now solve the equation x=\frac{-21±9}{-10} when ± is minus. Subtract 9 from -21.
x=3
Divide -30 by -10.
x=\frac{6}{5} x=3
The equation is now solved.
x=\frac{6}{5}
Variable x cannot be equal to 3.
2=\left(x-3\right)\left(x-1\right)\left(-5\right)+x-1
Variable x cannot be equal to any of the values 1,3 since division by zero is not defined. Multiply both sides of the equation by \left(x-3\right)\left(x-1\right), the least common multiple of \left(x-1\right)\left(x-3\right),x-3.
2=\left(x^{2}-4x+3\right)\left(-5\right)+x-1
Use the distributive property to multiply x-3 by x-1 and combine like terms.
2=-5x^{2}+20x-15+x-1
Use the distributive property to multiply x^{2}-4x+3 by -5.
2=-5x^{2}+21x-15-1
Combine 20x and x to get 21x.
2=-5x^{2}+21x-16
Subtract 1 from -15 to get -16.
-5x^{2}+21x-16=2
Swap sides so that all variable terms are on the left hand side.
-5x^{2}+21x=2+16
Add 16 to both sides.
-5x^{2}+21x=18
Add 2 and 16 to get 18.
\frac{-5x^{2}+21x}{-5}=\frac{18}{-5}
Divide both sides by -5.
x^{2}+\frac{21}{-5}x=\frac{18}{-5}
Dividing by -5 undoes the multiplication by -5.
x^{2}-\frac{21}{5}x=\frac{18}{-5}
Divide 21 by -5.
x^{2}-\frac{21}{5}x=-\frac{18}{5}
Divide 18 by -5.
x^{2}-\frac{21}{5}x+\left(-\frac{21}{10}\right)^{2}=-\frac{18}{5}+\left(-\frac{21}{10}\right)^{2}
Divide -\frac{21}{5}, the coefficient of the x term, by 2 to get -\frac{21}{10}. Then add the square of -\frac{21}{10} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{21}{5}x+\frac{441}{100}=-\frac{18}{5}+\frac{441}{100}
Square -\frac{21}{10} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{21}{5}x+\frac{441}{100}=\frac{81}{100}
Add -\frac{18}{5} to \frac{441}{100} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{21}{10}\right)^{2}=\frac{81}{100}
Factor x^{2}-\frac{21}{5}x+\frac{441}{100}. 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{21}{10}\right)^{2}}=\sqrt{\frac{81}{100}}
Take the square root of both sides of the equation.
x-\frac{21}{10}=\frac{9}{10} x-\frac{21}{10}=-\frac{9}{10}
Simplify.
x=3 x=\frac{6}{5}
Add \frac{21}{10} to both sides of the equation.
x=\frac{6}{5}
Variable x cannot be equal to 3.
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