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2\left(3x-7\right)+\left(x-5\right)x=2\times 8
Variable x cannot be equal to 5 since division by zero is not defined. Multiply both sides of the equation by 2\left(x-5\right), the least common multiple of x-5,2.
6x-14+\left(x-5\right)x=2\times 8
Use the distributive property to multiply 2 by 3x-7.
6x-14+x^{2}-5x=2\times 8
Use the distributive property to multiply x-5 by x.
x-14+x^{2}=2\times 8
Combine 6x and -5x to get x.
x-14+x^{2}=16
Multiply 2 and 8 to get 16.
x-14+x^{2}-16=0
Subtract 16 from both sides.
x-30+x^{2}=0
Subtract 16 from -14 to get -30.
x^{2}+x-30=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{-1±\sqrt{1^{2}-4\left(-30\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 1 for b, and -30 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-1±\sqrt{1-4\left(-30\right)}}{2}
Square 1.
x=\frac{-1±\sqrt{1+120}}{2}
Multiply -4 times -30.
x=\frac{-1±\sqrt{121}}{2}
Add 1 to 120.
x=\frac{-1±11}{2}
Take the square root of 121.
x=\frac{10}{2}
Now solve the equation x=\frac{-1±11}{2} when ± is plus. Add -1 to 11.
x=5
Divide 10 by 2.
x=-\frac{12}{2}
Now solve the equation x=\frac{-1±11}{2} when ± is minus. Subtract 11 from -1.
x=-6
Divide -12 by 2.
x=5 x=-6
The equation is now solved.
x=-6
Variable x cannot be equal to 5.
2\left(3x-7\right)+\left(x-5\right)x=2\times 8
Variable x cannot be equal to 5 since division by zero is not defined. Multiply both sides of the equation by 2\left(x-5\right), the least common multiple of x-5,2.
6x-14+\left(x-5\right)x=2\times 8
Use the distributive property to multiply 2 by 3x-7.
6x-14+x^{2}-5x=2\times 8
Use the distributive property to multiply x-5 by x.
x-14+x^{2}=2\times 8
Combine 6x and -5x to get x.
x-14+x^{2}=16
Multiply 2 and 8 to get 16.
x+x^{2}=16+14
Add 14 to both sides.
x+x^{2}=30
Add 16 and 14 to get 30.
x^{2}+x=30
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.
x^{2}+x+\left(\frac{1}{2}\right)^{2}=30+\left(\frac{1}{2}\right)^{2}
Divide 1, the coefficient of the x term, by 2 to get \frac{1}{2}. Then add the square of \frac{1}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+x+\frac{1}{4}=30+\frac{1}{4}
Square \frac{1}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}+x+\frac{1}{4}=\frac{121}{4}
Add 30 to \frac{1}{4}.
\left(x+\frac{1}{2}\right)^{2}=\frac{121}{4}
Factor x^{2}+x+\frac{1}{4}. 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{1}{2}\right)^{2}}=\sqrt{\frac{121}{4}}
Take the square root of both sides of the equation.
x+\frac{1}{2}=\frac{11}{2} x+\frac{1}{2}=-\frac{11}{2}
Simplify.
x=5 x=-6
Subtract \frac{1}{2} from both sides of the equation.
x=-6
Variable x cannot be equal to 5.