Solve for x
x = \frac{\sqrt{1561} + 41}{10} \approx 8.050949253
x=\frac{41-\sqrt{1561}}{10}\approx 0.149050747
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\left(2x+4\right)\times 5x+\left(6x-6\right)\times 6=15\left(x-1\right)\left(x+2\right)
Variable x cannot be equal to any of the values -2,1 since division by zero is not defined. Multiply both sides of the equation by 6\left(x-1\right)\left(x+2\right), the least common multiple of 3\left(x-1\right),x+2,2.
\left(10x+20\right)x+\left(6x-6\right)\times 6=15\left(x-1\right)\left(x+2\right)
Use the distributive property to multiply 2x+4 by 5.
10x^{2}+20x+\left(6x-6\right)\times 6=15\left(x-1\right)\left(x+2\right)
Use the distributive property to multiply 10x+20 by x.
10x^{2}+20x+36x-36=15\left(x-1\right)\left(x+2\right)
Use the distributive property to multiply 6x-6 by 6.
10x^{2}+56x-36=15\left(x-1\right)\left(x+2\right)
Combine 20x and 36x to get 56x.
10x^{2}+56x-36=\left(15x-15\right)\left(x+2\right)
Use the distributive property to multiply 15 by x-1.
10x^{2}+56x-36=15x^{2}+15x-30
Use the distributive property to multiply 15x-15 by x+2 and combine like terms.
10x^{2}+56x-36-15x^{2}=15x-30
Subtract 15x^{2} from both sides.
-5x^{2}+56x-36=15x-30
Combine 10x^{2} and -15x^{2} to get -5x^{2}.
-5x^{2}+56x-36-15x=-30
Subtract 15x from both sides.
-5x^{2}+41x-36=-30
Combine 56x and -15x to get 41x.
-5x^{2}+41x-36+30=0
Add 30 to both sides.
-5x^{2}+41x-6=0
Add -36 and 30 to get -6.
x=\frac{-41±\sqrt{41^{2}-4\left(-5\right)\left(-6\right)}}{2\left(-5\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -5 for a, 41 for b, and -6 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-41±\sqrt{1681-4\left(-5\right)\left(-6\right)}}{2\left(-5\right)}
Square 41.
x=\frac{-41±\sqrt{1681+20\left(-6\right)}}{2\left(-5\right)}
Multiply -4 times -5.
x=\frac{-41±\sqrt{1681-120}}{2\left(-5\right)}
Multiply 20 times -6.
x=\frac{-41±\sqrt{1561}}{2\left(-5\right)}
Add 1681 to -120.
x=\frac{-41±\sqrt{1561}}{-10}
Multiply 2 times -5.
x=\frac{\sqrt{1561}-41}{-10}
Now solve the equation x=\frac{-41±\sqrt{1561}}{-10} when ± is plus. Add -41 to \sqrt{1561}.
x=\frac{41-\sqrt{1561}}{10}
Divide -41+\sqrt{1561} by -10.
x=\frac{-\sqrt{1561}-41}{-10}
Now solve the equation x=\frac{-41±\sqrt{1561}}{-10} when ± is minus. Subtract \sqrt{1561} from -41.
x=\frac{\sqrt{1561}+41}{10}
Divide -41-\sqrt{1561} by -10.
x=\frac{41-\sqrt{1561}}{10} x=\frac{\sqrt{1561}+41}{10}
The equation is now solved.
\left(2x+4\right)\times 5x+\left(6x-6\right)\times 6=15\left(x-1\right)\left(x+2\right)
Variable x cannot be equal to any of the values -2,1 since division by zero is not defined. Multiply both sides of the equation by 6\left(x-1\right)\left(x+2\right), the least common multiple of 3\left(x-1\right),x+2,2.
\left(10x+20\right)x+\left(6x-6\right)\times 6=15\left(x-1\right)\left(x+2\right)
Use the distributive property to multiply 2x+4 by 5.
10x^{2}+20x+\left(6x-6\right)\times 6=15\left(x-1\right)\left(x+2\right)
Use the distributive property to multiply 10x+20 by x.
10x^{2}+20x+36x-36=15\left(x-1\right)\left(x+2\right)
Use the distributive property to multiply 6x-6 by 6.
10x^{2}+56x-36=15\left(x-1\right)\left(x+2\right)
Combine 20x and 36x to get 56x.
10x^{2}+56x-36=\left(15x-15\right)\left(x+2\right)
Use the distributive property to multiply 15 by x-1.
10x^{2}+56x-36=15x^{2}+15x-30
Use the distributive property to multiply 15x-15 by x+2 and combine like terms.
10x^{2}+56x-36-15x^{2}=15x-30
Subtract 15x^{2} from both sides.
-5x^{2}+56x-36=15x-30
Combine 10x^{2} and -15x^{2} to get -5x^{2}.
-5x^{2}+56x-36-15x=-30
Subtract 15x from both sides.
-5x^{2}+41x-36=-30
Combine 56x and -15x to get 41x.
-5x^{2}+41x=-30+36
Add 36 to both sides.
-5x^{2}+41x=6
Add -30 and 36 to get 6.
\frac{-5x^{2}+41x}{-5}=\frac{6}{-5}
Divide both sides by -5.
x^{2}+\frac{41}{-5}x=\frac{6}{-5}
Dividing by -5 undoes the multiplication by -5.
x^{2}-\frac{41}{5}x=\frac{6}{-5}
Divide 41 by -5.
x^{2}-\frac{41}{5}x=-\frac{6}{5}
Divide 6 by -5.
x^{2}-\frac{41}{5}x+\left(-\frac{41}{10}\right)^{2}=-\frac{6}{5}+\left(-\frac{41}{10}\right)^{2}
Divide -\frac{41}{5}, the coefficient of the x term, by 2 to get -\frac{41}{10}. Then add the square of -\frac{41}{10} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{41}{5}x+\frac{1681}{100}=-\frac{6}{5}+\frac{1681}{100}
Square -\frac{41}{10} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{41}{5}x+\frac{1681}{100}=\frac{1561}{100}
Add -\frac{6}{5} to \frac{1681}{100} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{41}{10}\right)^{2}=\frac{1561}{100}
Factor x^{2}-\frac{41}{5}x+\frac{1681}{100}. 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{41}{10}\right)^{2}}=\sqrt{\frac{1561}{100}}
Take the square root of both sides of the equation.
x-\frac{41}{10}=\frac{\sqrt{1561}}{10} x-\frac{41}{10}=-\frac{\sqrt{1561}}{10}
Simplify.
x=\frac{\sqrt{1561}+41}{10} x=\frac{41-\sqrt{1561}}{10}
Add \frac{41}{10} to both sides of the equation.
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