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2xx-\left(x-5\right)\times 3=15+7
Variable x cannot be equal to any of the values 0,5 since division by zero is not defined. Multiply both sides of the equation by 2x\left(x-5\right), the least common multiple of x-5,2x,2x^{2}-10x.
2x^{2}-\left(x-5\right)\times 3=15+7
Multiply x and x to get x^{2}.
2x^{2}-\left(3x-15\right)=15+7
Use the distributive property to multiply x-5 by 3.
2x^{2}-3x+15=15+7
To find the opposite of 3x-15, find the opposite of each term.
2x^{2}-3x+15=22
Add 15 and 7 to get 22.
2x^{2}-3x+15-22=0
Subtract 22 from both sides.
2x^{2}-3x-7=0
Subtract 22 from 15 to get -7.
x=\frac{-\left(-3\right)±\sqrt{\left(-3\right)^{2}-4\times 2\left(-7\right)}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, -3 for b, and -7 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-3\right)±\sqrt{9-4\times 2\left(-7\right)}}{2\times 2}
Square -3.
x=\frac{-\left(-3\right)±\sqrt{9-8\left(-7\right)}}{2\times 2}
Multiply -4 times 2.
x=\frac{-\left(-3\right)±\sqrt{9+56}}{2\times 2}
Multiply -8 times -7.
x=\frac{-\left(-3\right)±\sqrt{65}}{2\times 2}
Add 9 to 56.
x=\frac{3±\sqrt{65}}{2\times 2}
The opposite of -3 is 3.
x=\frac{3±\sqrt{65}}{4}
Multiply 2 times 2.
x=\frac{\sqrt{65}+3}{4}
Now solve the equation x=\frac{3±\sqrt{65}}{4} when ± is plus. Add 3 to \sqrt{65}.
x=\frac{3-\sqrt{65}}{4}
Now solve the equation x=\frac{3±\sqrt{65}}{4} when ± is minus. Subtract \sqrt{65} from 3.
x=\frac{\sqrt{65}+3}{4} x=\frac{3-\sqrt{65}}{4}
The equation is now solved.
2xx-\left(x-5\right)\times 3=15+7
Variable x cannot be equal to any of the values 0,5 since division by zero is not defined. Multiply both sides of the equation by 2x\left(x-5\right), the least common multiple of x-5,2x,2x^{2}-10x.
2x^{2}-\left(x-5\right)\times 3=15+7
Multiply x and x to get x^{2}.
2x^{2}-\left(3x-15\right)=15+7
Use the distributive property to multiply x-5 by 3.
2x^{2}-3x+15=15+7
To find the opposite of 3x-15, find the opposite of each term.
2x^{2}-3x+15=22
Add 15 and 7 to get 22.
2x^{2}-3x=22-15
Subtract 15 from both sides.
2x^{2}-3x=7
Subtract 15 from 22 to get 7.
\frac{2x^{2}-3x}{2}=\frac{7}{2}
Divide both sides by 2.
x^{2}-\frac{3}{2}x=\frac{7}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}-\frac{3}{2}x+\left(-\frac{3}{4}\right)^{2}=\frac{7}{2}+\left(-\frac{3}{4}\right)^{2}
Divide -\frac{3}{2}, the coefficient of the x term, by 2 to get -\frac{3}{4}. Then add the square of -\frac{3}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{3}{2}x+\frac{9}{16}=\frac{7}{2}+\frac{9}{16}
Square -\frac{3}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{3}{2}x+\frac{9}{16}=\frac{65}{16}
Add \frac{7}{2} to \frac{9}{16} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{3}{4}\right)^{2}=\frac{65}{16}
Factor x^{2}-\frac{3}{2}x+\frac{9}{16}. 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{3}{4}\right)^{2}}=\sqrt{\frac{65}{16}}
Take the square root of both sides of the equation.
x-\frac{3}{4}=\frac{\sqrt{65}}{4} x-\frac{3}{4}=-\frac{\sqrt{65}}{4}
Simplify.
x=\frac{\sqrt{65}+3}{4} x=\frac{3-\sqrt{65}}{4}
Add \frac{3}{4} to both sides of the equation.