Solve for x
x=-2
x=12
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x\left(x+6\right)\times 5-x\left(x-2\right)\times 3=\left(x-2\right)\left(x+6\right)\times 4
Variable x cannot be equal to any of the values -6,0,2 since division by zero is not defined. Multiply both sides of the equation by x\left(x-2\right)\left(x+6\right), the least common multiple of x-2,x+6,x.
\left(x^{2}+6x\right)\times 5-x\left(x-2\right)\times 3=\left(x-2\right)\left(x+6\right)\times 4
Use the distributive property to multiply x by x+6.
5x^{2}+30x-x\left(x-2\right)\times 3=\left(x-2\right)\left(x+6\right)\times 4
Use the distributive property to multiply x^{2}+6x by 5.
5x^{2}+30x-\left(x^{2}-2x\right)\times 3=\left(x-2\right)\left(x+6\right)\times 4
Use the distributive property to multiply x by x-2.
5x^{2}+30x-\left(3x^{2}-6x\right)=\left(x-2\right)\left(x+6\right)\times 4
Use the distributive property to multiply x^{2}-2x by 3.
5x^{2}+30x-3x^{2}+6x=\left(x-2\right)\left(x+6\right)\times 4
To find the opposite of 3x^{2}-6x, find the opposite of each term.
2x^{2}+30x+6x=\left(x-2\right)\left(x+6\right)\times 4
Combine 5x^{2} and -3x^{2} to get 2x^{2}.
2x^{2}+36x=\left(x-2\right)\left(x+6\right)\times 4
Combine 30x and 6x to get 36x.
2x^{2}+36x=\left(x^{2}+4x-12\right)\times 4
Use the distributive property to multiply x-2 by x+6 and combine like terms.
2x^{2}+36x=4x^{2}+16x-48
Use the distributive property to multiply x^{2}+4x-12 by 4.
2x^{2}+36x-4x^{2}=16x-48
Subtract 4x^{2} from both sides.
-2x^{2}+36x=16x-48
Combine 2x^{2} and -4x^{2} to get -2x^{2}.
-2x^{2}+36x-16x=-48
Subtract 16x from both sides.
-2x^{2}+20x=-48
Combine 36x and -16x to get 20x.
-2x^{2}+20x+48=0
Add 48 to both sides.
x=\frac{-20±\sqrt{20^{2}-4\left(-2\right)\times 48}}{2\left(-2\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -2 for a, 20 for b, and 48 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-20±\sqrt{400-4\left(-2\right)\times 48}}{2\left(-2\right)}
Square 20.
x=\frac{-20±\sqrt{400+8\times 48}}{2\left(-2\right)}
Multiply -4 times -2.
x=\frac{-20±\sqrt{400+384}}{2\left(-2\right)}
Multiply 8 times 48.
x=\frac{-20±\sqrt{784}}{2\left(-2\right)}
Add 400 to 384.
x=\frac{-20±28}{2\left(-2\right)}
Take the square root of 784.
x=\frac{-20±28}{-4}
Multiply 2 times -2.
x=\frac{8}{-4}
Now solve the equation x=\frac{-20±28}{-4} when ± is plus. Add -20 to 28.
x=-2
Divide 8 by -4.
x=-\frac{48}{-4}
Now solve the equation x=\frac{-20±28}{-4} when ± is minus. Subtract 28 from -20.
x=12
Divide -48 by -4.
x=-2 x=12
The equation is now solved.
x\left(x+6\right)\times 5-x\left(x-2\right)\times 3=\left(x-2\right)\left(x+6\right)\times 4
Variable x cannot be equal to any of the values -6,0,2 since division by zero is not defined. Multiply both sides of the equation by x\left(x-2\right)\left(x+6\right), the least common multiple of x-2,x+6,x.
\left(x^{2}+6x\right)\times 5-x\left(x-2\right)\times 3=\left(x-2\right)\left(x+6\right)\times 4
Use the distributive property to multiply x by x+6.
5x^{2}+30x-x\left(x-2\right)\times 3=\left(x-2\right)\left(x+6\right)\times 4
Use the distributive property to multiply x^{2}+6x by 5.
5x^{2}+30x-\left(x^{2}-2x\right)\times 3=\left(x-2\right)\left(x+6\right)\times 4
Use the distributive property to multiply x by x-2.
5x^{2}+30x-\left(3x^{2}-6x\right)=\left(x-2\right)\left(x+6\right)\times 4
Use the distributive property to multiply x^{2}-2x by 3.
5x^{2}+30x-3x^{2}+6x=\left(x-2\right)\left(x+6\right)\times 4
To find the opposite of 3x^{2}-6x, find the opposite of each term.
2x^{2}+30x+6x=\left(x-2\right)\left(x+6\right)\times 4
Combine 5x^{2} and -3x^{2} to get 2x^{2}.
2x^{2}+36x=\left(x-2\right)\left(x+6\right)\times 4
Combine 30x and 6x to get 36x.
2x^{2}+36x=\left(x^{2}+4x-12\right)\times 4
Use the distributive property to multiply x-2 by x+6 and combine like terms.
2x^{2}+36x=4x^{2}+16x-48
Use the distributive property to multiply x^{2}+4x-12 by 4.
2x^{2}+36x-4x^{2}=16x-48
Subtract 4x^{2} from both sides.
-2x^{2}+36x=16x-48
Combine 2x^{2} and -4x^{2} to get -2x^{2}.
-2x^{2}+36x-16x=-48
Subtract 16x from both sides.
-2x^{2}+20x=-48
Combine 36x and -16x to get 20x.
\frac{-2x^{2}+20x}{-2}=-\frac{48}{-2}
Divide both sides by -2.
x^{2}+\frac{20}{-2}x=-\frac{48}{-2}
Dividing by -2 undoes the multiplication by -2.
x^{2}-10x=-\frac{48}{-2}
Divide 20 by -2.
x^{2}-10x=24
Divide -48 by -2.
x^{2}-10x+\left(-5\right)^{2}=24+\left(-5\right)^{2}
Divide -10, the coefficient of the x term, by 2 to get -5. Then add the square of -5 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-10x+25=24+25
Square -5.
x^{2}-10x+25=49
Add 24 to 25.
\left(x-5\right)^{2}=49
Factor x^{2}-10x+25. 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-5\right)^{2}}=\sqrt{49}
Take the square root of both sides of the equation.
x-5=7 x-5=-7
Simplify.
x=12 x=-2
Add 5 to both sides of the equation.
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