Solve for x
x=-3
x=6
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\left(x-2\right)x=5\left(x+2\right)+5\left(x-2\right)\left(-\frac{4}{5}\right)
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by 5\left(x-2\right), the least common multiple of 5,x-2.
x^{2}-2x=5\left(x+2\right)+5\left(x-2\right)\left(-\frac{4}{5}\right)
Use the distributive property to multiply x-2 by x.
x^{2}-2x=5x+10+5\left(x-2\right)\left(-\frac{4}{5}\right)
Use the distributive property to multiply 5 by x+2.
x^{2}-2x=5x+10-4\left(x-2\right)
Multiply 5 and -\frac{4}{5} to get -4.
x^{2}-2x=5x+10-4x+8
Use the distributive property to multiply -4 by x-2.
x^{2}-2x=x+10+8
Combine 5x and -4x to get x.
x^{2}-2x=x+18
Add 10 and 8 to get 18.
x^{2}-2x-x=18
Subtract x from both sides.
x^{2}-3x=18
Combine -2x and -x to get -3x.
x^{2}-3x-18=0
Subtract 18 from both sides.
x=\frac{-\left(-3\right)±\sqrt{\left(-3\right)^{2}-4\left(-18\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -3 for b, and -18 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-3\right)±\sqrt{9-4\left(-18\right)}}{2}
Square -3.
x=\frac{-\left(-3\right)±\sqrt{9+72}}{2}
Multiply -4 times -18.
x=\frac{-\left(-3\right)±\sqrt{81}}{2}
Add 9 to 72.
x=\frac{-\left(-3\right)±9}{2}
Take the square root of 81.
x=\frac{3±9}{2}
The opposite of -3 is 3.
x=\frac{12}{2}
Now solve the equation x=\frac{3±9}{2} when ± is plus. Add 3 to 9.
x=6
Divide 12 by 2.
x=-\frac{6}{2}
Now solve the equation x=\frac{3±9}{2} when ± is minus. Subtract 9 from 3.
x=-3
Divide -6 by 2.
x=6 x=-3
The equation is now solved.
\left(x-2\right)x=5\left(x+2\right)+5\left(x-2\right)\left(-\frac{4}{5}\right)
Variable x cannot be equal to 2 since division by zero is not defined. Multiply both sides of the equation by 5\left(x-2\right), the least common multiple of 5,x-2.
x^{2}-2x=5\left(x+2\right)+5\left(x-2\right)\left(-\frac{4}{5}\right)
Use the distributive property to multiply x-2 by x.
x^{2}-2x=5x+10+5\left(x-2\right)\left(-\frac{4}{5}\right)
Use the distributive property to multiply 5 by x+2.
x^{2}-2x=5x+10-4\left(x-2\right)
Multiply 5 and -\frac{4}{5} to get -4.
x^{2}-2x=5x+10-4x+8
Use the distributive property to multiply -4 by x-2.
x^{2}-2x=x+10+8
Combine 5x and -4x to get x.
x^{2}-2x=x+18
Add 10 and 8 to get 18.
x^{2}-2x-x=18
Subtract x from both sides.
x^{2}-3x=18
Combine -2x and -x to get -3x.
x^{2}-3x+\left(-\frac{3}{2}\right)^{2}=18+\left(-\frac{3}{2}\right)^{2}
Divide -3, the coefficient of the x term, by 2 to get -\frac{3}{2}. Then add the square of -\frac{3}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-3x+\frac{9}{4}=18+\frac{9}{4}
Square -\frac{3}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-3x+\frac{9}{4}=\frac{81}{4}
Add 18 to \frac{9}{4}.
\left(x-\frac{3}{2}\right)^{2}=\frac{81}{4}
Factor x^{2}-3x+\frac{9}{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{3}{2}\right)^{2}}=\sqrt{\frac{81}{4}}
Take the square root of both sides of the equation.
x-\frac{3}{2}=\frac{9}{2} x-\frac{3}{2}=-\frac{9}{2}
Simplify.
x=6 x=-3
Add \frac{3}{2} to both sides of the equation.
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