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\left(5x-50\right)\times 5-\left(5x+20\right)\times 2=3\left(x-10\right)\left(x+4\right)
Variable x cannot be equal to any of the values -4,10 since division by zero is not defined. Multiply both sides of the equation by 5\left(x-10\right)\left(x+4\right), the least common multiple of x+4,x-10,5.
25x-250-\left(5x+20\right)\times 2=3\left(x-10\right)\left(x+4\right)
Use the distributive property to multiply 5x-50 by 5.
25x-250-\left(10x+40\right)=3\left(x-10\right)\left(x+4\right)
Use the distributive property to multiply 5x+20 by 2.
25x-250-10x-40=3\left(x-10\right)\left(x+4\right)
To find the opposite of 10x+40, find the opposite of each term.
15x-250-40=3\left(x-10\right)\left(x+4\right)
Combine 25x and -10x to get 15x.
15x-290=3\left(x-10\right)\left(x+4\right)
Subtract 40 from -250 to get -290.
15x-290=\left(3x-30\right)\left(x+4\right)
Use the distributive property to multiply 3 by x-10.
15x-290=3x^{2}-18x-120
Use the distributive property to multiply 3x-30 by x+4 and combine like terms.
15x-290-3x^{2}=-18x-120
Subtract 3x^{2} from both sides.
15x-290-3x^{2}+18x=-120
Add 18x to both sides.
33x-290-3x^{2}=-120
Combine 15x and 18x to get 33x.
33x-290-3x^{2}+120=0
Add 120 to both sides.
33x-170-3x^{2}=0
Add -290 and 120 to get -170.
-3x^{2}+33x-170=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{-33±\sqrt{33^{2}-4\left(-3\right)\left(-170\right)}}{2\left(-3\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -3 for a, 33 for b, and -170 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-33±\sqrt{1089-4\left(-3\right)\left(-170\right)}}{2\left(-3\right)}
Square 33.
x=\frac{-33±\sqrt{1089+12\left(-170\right)}}{2\left(-3\right)}
Multiply -4 times -3.
x=\frac{-33±\sqrt{1089-2040}}{2\left(-3\right)}
Multiply 12 times -170.
x=\frac{-33±\sqrt{-951}}{2\left(-3\right)}
Add 1089 to -2040.
x=\frac{-33±\sqrt{951}i}{2\left(-3\right)}
Take the square root of -951.
x=\frac{-33±\sqrt{951}i}{-6}
Multiply 2 times -3.
x=\frac{-33+\sqrt{951}i}{-6}
Now solve the equation x=\frac{-33±\sqrt{951}i}{-6} when ± is plus. Add -33 to i\sqrt{951}.
x=-\frac{\sqrt{951}i}{6}+\frac{11}{2}
Divide -33+i\sqrt{951} by -6.
x=\frac{-\sqrt{951}i-33}{-6}
Now solve the equation x=\frac{-33±\sqrt{951}i}{-6} when ± is minus. Subtract i\sqrt{951} from -33.
x=\frac{\sqrt{951}i}{6}+\frac{11}{2}
Divide -33-i\sqrt{951} by -6.
x=-\frac{\sqrt{951}i}{6}+\frac{11}{2} x=\frac{\sqrt{951}i}{6}+\frac{11}{2}
The equation is now solved.
\left(5x-50\right)\times 5-\left(5x+20\right)\times 2=3\left(x-10\right)\left(x+4\right)
Variable x cannot be equal to any of the values -4,10 since division by zero is not defined. Multiply both sides of the equation by 5\left(x-10\right)\left(x+4\right), the least common multiple of x+4,x-10,5.
25x-250-\left(5x+20\right)\times 2=3\left(x-10\right)\left(x+4\right)
Use the distributive property to multiply 5x-50 by 5.
25x-250-\left(10x+40\right)=3\left(x-10\right)\left(x+4\right)
Use the distributive property to multiply 5x+20 by 2.
25x-250-10x-40=3\left(x-10\right)\left(x+4\right)
To find the opposite of 10x+40, find the opposite of each term.
15x-250-40=3\left(x-10\right)\left(x+4\right)
Combine 25x and -10x to get 15x.
15x-290=3\left(x-10\right)\left(x+4\right)
Subtract 40 from -250 to get -290.
15x-290=\left(3x-30\right)\left(x+4\right)
Use the distributive property to multiply 3 by x-10.
15x-290=3x^{2}-18x-120
Use the distributive property to multiply 3x-30 by x+4 and combine like terms.
15x-290-3x^{2}=-18x-120
Subtract 3x^{2} from both sides.
15x-290-3x^{2}+18x=-120
Add 18x to both sides.
33x-290-3x^{2}=-120
Combine 15x and 18x to get 33x.
33x-3x^{2}=-120+290
Add 290 to both sides.
33x-3x^{2}=170
Add -120 and 290 to get 170.
-3x^{2}+33x=170
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.
\frac{-3x^{2}+33x}{-3}=\frac{170}{-3}
Divide both sides by -3.
x^{2}+\frac{33}{-3}x=\frac{170}{-3}
Dividing by -3 undoes the multiplication by -3.
x^{2}-11x=\frac{170}{-3}
Divide 33 by -3.
x^{2}-11x=-\frac{170}{3}
Divide 170 by -3.
x^{2}-11x+\left(-\frac{11}{2}\right)^{2}=-\frac{170}{3}+\left(-\frac{11}{2}\right)^{2}
Divide -11, the coefficient of the x term, by 2 to get -\frac{11}{2}. Then add the square of -\frac{11}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-11x+\frac{121}{4}=-\frac{170}{3}+\frac{121}{4}
Square -\frac{11}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-11x+\frac{121}{4}=-\frac{317}{12}
Add -\frac{170}{3} to \frac{121}{4} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{11}{2}\right)^{2}=-\frac{317}{12}
Factor x^{2}-11x+\frac{121}{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{11}{2}\right)^{2}}=\sqrt{-\frac{317}{12}}
Take the square root of both sides of the equation.
x-\frac{11}{2}=\frac{\sqrt{951}i}{6} x-\frac{11}{2}=-\frac{\sqrt{951}i}{6}
Simplify.
x=\frac{\sqrt{951}i}{6}+\frac{11}{2} x=-\frac{\sqrt{951}i}{6}+\frac{11}{2}
Add \frac{11}{2} to both sides of the equation.