Solve for x
x=-2
x=12
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3x\left(x-2\right)-2\left(x^{2}+2\right)=4\left(x+5\right)
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 12x, the least common multiple of 4,6x,3x.
3x^{2}-6x-2\left(x^{2}+2\right)=4\left(x+5\right)
Use the distributive property to multiply 3x by x-2.
3x^{2}-6x-2x^{2}-4=4\left(x+5\right)
Use the distributive property to multiply -2 by x^{2}+2.
x^{2}-6x-4=4\left(x+5\right)
Combine 3x^{2} and -2x^{2} to get x^{2}.
x^{2}-6x-4=4x+20
Use the distributive property to multiply 4 by x+5.
x^{2}-6x-4-4x=20
Subtract 4x from both sides.
x^{2}-10x-4=20
Combine -6x and -4x to get -10x.
x^{2}-10x-4-20=0
Subtract 20 from both sides.
x^{2}-10x-24=0
Subtract 20 from -4 to get -24.
a+b=-10 ab=-24
To solve the equation, factor x^{2}-10x-24 using formula x^{2}+\left(a+b\right)x+ab=\left(x+a\right)\left(x+b\right). To find a and b, set up a system to be solved.
1,-24 2,-12 3,-8 4,-6
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product -24.
1-24=-23 2-12=-10 3-8=-5 4-6=-2
Calculate the sum for each pair.
a=-12 b=2
The solution is the pair that gives sum -10.
\left(x-12\right)\left(x+2\right)
Rewrite factored expression \left(x+a\right)\left(x+b\right) using the obtained values.
x=12 x=-2
To find equation solutions, solve x-12=0 and x+2=0.
3x\left(x-2\right)-2\left(x^{2}+2\right)=4\left(x+5\right)
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 12x, the least common multiple of 4,6x,3x.
3x^{2}-6x-2\left(x^{2}+2\right)=4\left(x+5\right)
Use the distributive property to multiply 3x by x-2.
3x^{2}-6x-2x^{2}-4=4\left(x+5\right)
Use the distributive property to multiply -2 by x^{2}+2.
x^{2}-6x-4=4\left(x+5\right)
Combine 3x^{2} and -2x^{2} to get x^{2}.
x^{2}-6x-4=4x+20
Use the distributive property to multiply 4 by x+5.
x^{2}-6x-4-4x=20
Subtract 4x from both sides.
x^{2}-10x-4=20
Combine -6x and -4x to get -10x.
x^{2}-10x-4-20=0
Subtract 20 from both sides.
x^{2}-10x-24=0
Subtract 20 from -4 to get -24.
a+b=-10 ab=1\left(-24\right)=-24
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as x^{2}+ax+bx-24. To find a and b, set up a system to be solved.
1,-24 2,-12 3,-8 4,-6
Since ab is negative, a and b have the opposite signs. Since a+b is negative, the negative number has greater absolute value than the positive. List all such integer pairs that give product -24.
1-24=-23 2-12=-10 3-8=-5 4-6=-2
Calculate the sum for each pair.
a=-12 b=2
The solution is the pair that gives sum -10.
\left(x^{2}-12x\right)+\left(2x-24\right)
Rewrite x^{2}-10x-24 as \left(x^{2}-12x\right)+\left(2x-24\right).
x\left(x-12\right)+2\left(x-12\right)
Factor out x in the first and 2 in the second group.
\left(x-12\right)\left(x+2\right)
Factor out common term x-12 by using distributive property.
x=12 x=-2
To find equation solutions, solve x-12=0 and x+2=0.
3x\left(x-2\right)-2\left(x^{2}+2\right)=4\left(x+5\right)
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 12x, the least common multiple of 4,6x,3x.
3x^{2}-6x-2\left(x^{2}+2\right)=4\left(x+5\right)
Use the distributive property to multiply 3x by x-2.
3x^{2}-6x-2x^{2}-4=4\left(x+5\right)
Use the distributive property to multiply -2 by x^{2}+2.
x^{2}-6x-4=4\left(x+5\right)
Combine 3x^{2} and -2x^{2} to get x^{2}.
x^{2}-6x-4=4x+20
Use the distributive property to multiply 4 by x+5.
x^{2}-6x-4-4x=20
Subtract 4x from both sides.
x^{2}-10x-4=20
Combine -6x and -4x to get -10x.
x^{2}-10x-4-20=0
Subtract 20 from both sides.
x^{2}-10x-24=0
Subtract 20 from -4 to get -24.
x=\frac{-\left(-10\right)±\sqrt{\left(-10\right)^{2}-4\left(-24\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -10 for b, and -24 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-10\right)±\sqrt{100-4\left(-24\right)}}{2}
Square -10.
x=\frac{-\left(-10\right)±\sqrt{100+96}}{2}
Multiply -4 times -24.
x=\frac{-\left(-10\right)±\sqrt{196}}{2}
Add 100 to 96.
x=\frac{-\left(-10\right)±14}{2}
Take the square root of 196.
x=\frac{10±14}{2}
The opposite of -10 is 10.
x=\frac{24}{2}
Now solve the equation x=\frac{10±14}{2} when ± is plus. Add 10 to 14.
x=12
Divide 24 by 2.
x=-\frac{4}{2}
Now solve the equation x=\frac{10±14}{2} when ± is minus. Subtract 14 from 10.
x=-2
Divide -4 by 2.
x=12 x=-2
The equation is now solved.
3x\left(x-2\right)-2\left(x^{2}+2\right)=4\left(x+5\right)
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 12x, the least common multiple of 4,6x,3x.
3x^{2}-6x-2\left(x^{2}+2\right)=4\left(x+5\right)
Use the distributive property to multiply 3x by x-2.
3x^{2}-6x-2x^{2}-4=4\left(x+5\right)
Use the distributive property to multiply -2 by x^{2}+2.
x^{2}-6x-4=4\left(x+5\right)
Combine 3x^{2} and -2x^{2} to get x^{2}.
x^{2}-6x-4=4x+20
Use the distributive property to multiply 4 by x+5.
x^{2}-6x-4-4x=20
Subtract 4x from both sides.
x^{2}-10x-4=20
Combine -6x and -4x to get -10x.
x^{2}-10x=20+4
Add 4 to both sides.
x^{2}-10x=24
Add 20 and 4 to get 24.
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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