Solve for x
x=-4
x=2
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2xx+\left(2x+4\right)\left(x+2\right)=5x\left(x+2\right)
Variable x cannot be equal to any of the values -2,0 since division by zero is not defined. Multiply both sides of the equation by 2x\left(x+2\right), the least common multiple of x+2,x,2.
2x^{2}+\left(2x+4\right)\left(x+2\right)=5x\left(x+2\right)
Multiply x and x to get x^{2}.
2x^{2}+2x^{2}+8x+8=5x\left(x+2\right)
Use the distributive property to multiply 2x+4 by x+2 and combine like terms.
4x^{2}+8x+8=5x\left(x+2\right)
Combine 2x^{2} and 2x^{2} to get 4x^{2}.
4x^{2}+8x+8=5x^{2}+10x
Use the distributive property to multiply 5x by x+2.
4x^{2}+8x+8-5x^{2}=10x
Subtract 5x^{2} from both sides.
-x^{2}+8x+8=10x
Combine 4x^{2} and -5x^{2} to get -x^{2}.
-x^{2}+8x+8-10x=0
Subtract 10x from both sides.
-x^{2}-2x+8=0
Combine 8x and -10x to get -2x.
a+b=-2 ab=-8=-8
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -x^{2}+ax+bx+8. To find a and b, set up a system to be solved.
1,-8 2,-4
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 -8.
1-8=-7 2-4=-2
Calculate the sum for each pair.
a=2 b=-4
The solution is the pair that gives sum -2.
\left(-x^{2}+2x\right)+\left(-4x+8\right)
Rewrite -x^{2}-2x+8 as \left(-x^{2}+2x\right)+\left(-4x+8\right).
x\left(-x+2\right)+4\left(-x+2\right)
Factor out x in the first and 4 in the second group.
\left(-x+2\right)\left(x+4\right)
Factor out common term -x+2 by using distributive property.
x=2 x=-4
To find equation solutions, solve -x+2=0 and x+4=0.
2xx+\left(2x+4\right)\left(x+2\right)=5x\left(x+2\right)
Variable x cannot be equal to any of the values -2,0 since division by zero is not defined. Multiply both sides of the equation by 2x\left(x+2\right), the least common multiple of x+2,x,2.
2x^{2}+\left(2x+4\right)\left(x+2\right)=5x\left(x+2\right)
Multiply x and x to get x^{2}.
2x^{2}+2x^{2}+8x+8=5x\left(x+2\right)
Use the distributive property to multiply 2x+4 by x+2 and combine like terms.
4x^{2}+8x+8=5x\left(x+2\right)
Combine 2x^{2} and 2x^{2} to get 4x^{2}.
4x^{2}+8x+8=5x^{2}+10x
Use the distributive property to multiply 5x by x+2.
4x^{2}+8x+8-5x^{2}=10x
Subtract 5x^{2} from both sides.
-x^{2}+8x+8=10x
Combine 4x^{2} and -5x^{2} to get -x^{2}.
-x^{2}+8x+8-10x=0
Subtract 10x from both sides.
-x^{2}-2x+8=0
Combine 8x and -10x to get -2x.
x=\frac{-\left(-2\right)±\sqrt{\left(-2\right)^{2}-4\left(-1\right)\times 8}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, -2 for b, and 8 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-2\right)±\sqrt{4-4\left(-1\right)\times 8}}{2\left(-1\right)}
Square -2.
x=\frac{-\left(-2\right)±\sqrt{4+4\times 8}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{-\left(-2\right)±\sqrt{4+32}}{2\left(-1\right)}
Multiply 4 times 8.
x=\frac{-\left(-2\right)±\sqrt{36}}{2\left(-1\right)}
Add 4 to 32.
x=\frac{-\left(-2\right)±6}{2\left(-1\right)}
Take the square root of 36.
x=\frac{2±6}{2\left(-1\right)}
The opposite of -2 is 2.
x=\frac{2±6}{-2}
Multiply 2 times -1.
x=\frac{8}{-2}
Now solve the equation x=\frac{2±6}{-2} when ± is plus. Add 2 to 6.
x=-4
Divide 8 by -2.
x=-\frac{4}{-2}
Now solve the equation x=\frac{2±6}{-2} when ± is minus. Subtract 6 from 2.
x=2
Divide -4 by -2.
x=-4 x=2
The equation is now solved.
2xx+\left(2x+4\right)\left(x+2\right)=5x\left(x+2\right)
Variable x cannot be equal to any of the values -2,0 since division by zero is not defined. Multiply both sides of the equation by 2x\left(x+2\right), the least common multiple of x+2,x,2.
2x^{2}+\left(2x+4\right)\left(x+2\right)=5x\left(x+2\right)
Multiply x and x to get x^{2}.
2x^{2}+2x^{2}+8x+8=5x\left(x+2\right)
Use the distributive property to multiply 2x+4 by x+2 and combine like terms.
4x^{2}+8x+8=5x\left(x+2\right)
Combine 2x^{2} and 2x^{2} to get 4x^{2}.
4x^{2}+8x+8=5x^{2}+10x
Use the distributive property to multiply 5x by x+2.
4x^{2}+8x+8-5x^{2}=10x
Subtract 5x^{2} from both sides.
-x^{2}+8x+8=10x
Combine 4x^{2} and -5x^{2} to get -x^{2}.
-x^{2}+8x+8-10x=0
Subtract 10x from both sides.
-x^{2}-2x+8=0
Combine 8x and -10x to get -2x.
-x^{2}-2x=-8
Subtract 8 from both sides. Anything subtracted from zero gives its negation.
\frac{-x^{2}-2x}{-1}=-\frac{8}{-1}
Divide both sides by -1.
x^{2}+\left(-\frac{2}{-1}\right)x=-\frac{8}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}+2x=-\frac{8}{-1}
Divide -2 by -1.
x^{2}+2x=8
Divide -8 by -1.
x^{2}+2x+1^{2}=8+1^{2}
Divide 2, the coefficient of the x term, by 2 to get 1. Then add the square of 1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+2x+1=8+1
Square 1.
x^{2}+2x+1=9
Add 8 to 1.
\left(x+1\right)^{2}=9
Factor x^{2}+2x+1. 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+1\right)^{2}}=\sqrt{9}
Take the square root of both sides of the equation.
x+1=3 x+1=-3
Simplify.
x=2 x=-4
Subtract 1 from both sides of the equation.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
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