Solve for x
x=2
x=\frac{3}{10}=0.3
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3=5x\left(2x-1\right)+\left(2x-1\right)\left(-9\right)
Variable x cannot be equal to \frac{1}{2} since division by zero is not defined. Multiply both sides of the equation by 2x-1.
3=10x^{2}-5x+\left(2x-1\right)\left(-9\right)
Use the distributive property to multiply 5x by 2x-1.
3=10x^{2}-5x-18x+9
Use the distributive property to multiply 2x-1 by -9.
3=10x^{2}-23x+9
Combine -5x and -18x to get -23x.
10x^{2}-23x+9=3
Swap sides so that all variable terms are on the left hand side.
10x^{2}-23x+9-3=0
Subtract 3 from both sides.
10x^{2}-23x+6=0
Subtract 3 from 9 to get 6.
x=\frac{-\left(-23\right)±\sqrt{\left(-23\right)^{2}-4\times 10\times 6}}{2\times 10}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 10 for a, -23 for b, and 6 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-23\right)±\sqrt{529-4\times 10\times 6}}{2\times 10}
Square -23.
x=\frac{-\left(-23\right)±\sqrt{529-40\times 6}}{2\times 10}
Multiply -4 times 10.
x=\frac{-\left(-23\right)±\sqrt{529-240}}{2\times 10}
Multiply -40 times 6.
x=\frac{-\left(-23\right)±\sqrt{289}}{2\times 10}
Add 529 to -240.
x=\frac{-\left(-23\right)±17}{2\times 10}
Take the square root of 289.
x=\frac{23±17}{2\times 10}
The opposite of -23 is 23.
x=\frac{23±17}{20}
Multiply 2 times 10.
x=\frac{40}{20}
Now solve the equation x=\frac{23±17}{20} when ± is plus. Add 23 to 17.
x=2
Divide 40 by 20.
x=\frac{6}{20}
Now solve the equation x=\frac{23±17}{20} when ± is minus. Subtract 17 from 23.
x=\frac{3}{10}
Reduce the fraction \frac{6}{20} to lowest terms by extracting and canceling out 2.
x=2 x=\frac{3}{10}
The equation is now solved.
3=5x\left(2x-1\right)+\left(2x-1\right)\left(-9\right)
Variable x cannot be equal to \frac{1}{2} since division by zero is not defined. Multiply both sides of the equation by 2x-1.
3=10x^{2}-5x+\left(2x-1\right)\left(-9\right)
Use the distributive property to multiply 5x by 2x-1.
3=10x^{2}-5x-18x+9
Use the distributive property to multiply 2x-1 by -9.
3=10x^{2}-23x+9
Combine -5x and -18x to get -23x.
10x^{2}-23x+9=3
Swap sides so that all variable terms are on the left hand side.
10x^{2}-23x=3-9
Subtract 9 from both sides.
10x^{2}-23x=-6
Subtract 9 from 3 to get -6.
\frac{10x^{2}-23x}{10}=-\frac{6}{10}
Divide both sides by 10.
x^{2}-\frac{23}{10}x=-\frac{6}{10}
Dividing by 10 undoes the multiplication by 10.
x^{2}-\frac{23}{10}x=-\frac{3}{5}
Reduce the fraction \frac{-6}{10} to lowest terms by extracting and canceling out 2.
x^{2}-\frac{23}{10}x+\left(-\frac{23}{20}\right)^{2}=-\frac{3}{5}+\left(-\frac{23}{20}\right)^{2}
Divide -\frac{23}{10}, the coefficient of the x term, by 2 to get -\frac{23}{20}. Then add the square of -\frac{23}{20} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{23}{10}x+\frac{529}{400}=-\frac{3}{5}+\frac{529}{400}
Square -\frac{23}{20} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{23}{10}x+\frac{529}{400}=\frac{289}{400}
Add -\frac{3}{5} to \frac{529}{400} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{23}{20}\right)^{2}=\frac{289}{400}
Factor x^{2}-\frac{23}{10}x+\frac{529}{400}. 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{23}{20}\right)^{2}}=\sqrt{\frac{289}{400}}
Take the square root of both sides of the equation.
x-\frac{23}{20}=\frac{17}{20} x-\frac{23}{20}=-\frac{17}{20}
Simplify.
x=2 x=\frac{3}{10}
Add \frac{23}{20} to both sides of the equation.
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