Solve for x
x=3
x=\frac{2}{11}\approx 0.181818182
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Polynomial
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\frac { 3 } { x } + \frac { 5 } { x - 2 } = \frac { 30 } { x + 2 }
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\left(x^{2}-4\right)\times 3+x\left(x+2\right)\times 5=x\left(x-2\right)\times 30
Variable x cannot be equal to any of the values -2,0,2 since division by zero is not defined. Multiply both sides of the equation by x\left(x-2\right)\left(x+2\right), the least common multiple of x,x-2,x+2.
3x^{2}-12+x\left(x+2\right)\times 5=x\left(x-2\right)\times 30
Use the distributive property to multiply x^{2}-4 by 3.
3x^{2}-12+\left(x^{2}+2x\right)\times 5=x\left(x-2\right)\times 30
Use the distributive property to multiply x by x+2.
3x^{2}-12+5x^{2}+10x=x\left(x-2\right)\times 30
Use the distributive property to multiply x^{2}+2x by 5.
8x^{2}-12+10x=x\left(x-2\right)\times 30
Combine 3x^{2} and 5x^{2} to get 8x^{2}.
8x^{2}-12+10x=\left(x^{2}-2x\right)\times 30
Use the distributive property to multiply x by x-2.
8x^{2}-12+10x=30x^{2}-60x
Use the distributive property to multiply x^{2}-2x by 30.
8x^{2}-12+10x-30x^{2}=-60x
Subtract 30x^{2} from both sides.
-22x^{2}-12+10x=-60x
Combine 8x^{2} and -30x^{2} to get -22x^{2}.
-22x^{2}-12+10x+60x=0
Add 60x to both sides.
-22x^{2}-12+70x=0
Combine 10x and 60x to get 70x.
-11x^{2}-6+35x=0
Divide both sides by 2.
-11x^{2}+35x-6=0
Rearrange the polynomial to put it in standard form. Place the terms in order from highest to lowest power.
a+b=35 ab=-11\left(-6\right)=66
To solve the equation, factor the left hand side by grouping. First, left hand side needs to be rewritten as -11x^{2}+ax+bx-6. To find a and b, set up a system to be solved.
1,66 2,33 3,22 6,11
Since ab is positive, a and b have the same sign. Since a+b is positive, a and b are both positive. List all such integer pairs that give product 66.
1+66=67 2+33=35 3+22=25 6+11=17
Calculate the sum for each pair.
a=33 b=2
The solution is the pair that gives sum 35.
\left(-11x^{2}+33x\right)+\left(2x-6\right)
Rewrite -11x^{2}+35x-6 as \left(-11x^{2}+33x\right)+\left(2x-6\right).
11x\left(-x+3\right)-2\left(-x+3\right)
Factor out 11x in the first and -2 in the second group.
\left(-x+3\right)\left(11x-2\right)
Factor out common term -x+3 by using distributive property.
x=3 x=\frac{2}{11}
To find equation solutions, solve -x+3=0 and 11x-2=0.
\left(x^{2}-4\right)\times 3+x\left(x+2\right)\times 5=x\left(x-2\right)\times 30
Variable x cannot be equal to any of the values -2,0,2 since division by zero is not defined. Multiply both sides of the equation by x\left(x-2\right)\left(x+2\right), the least common multiple of x,x-2,x+2.
3x^{2}-12+x\left(x+2\right)\times 5=x\left(x-2\right)\times 30
Use the distributive property to multiply x^{2}-4 by 3.
3x^{2}-12+\left(x^{2}+2x\right)\times 5=x\left(x-2\right)\times 30
Use the distributive property to multiply x by x+2.
3x^{2}-12+5x^{2}+10x=x\left(x-2\right)\times 30
Use the distributive property to multiply x^{2}+2x by 5.
8x^{2}-12+10x=x\left(x-2\right)\times 30
Combine 3x^{2} and 5x^{2} to get 8x^{2}.
8x^{2}-12+10x=\left(x^{2}-2x\right)\times 30
Use the distributive property to multiply x by x-2.
8x^{2}-12+10x=30x^{2}-60x
Use the distributive property to multiply x^{2}-2x by 30.
8x^{2}-12+10x-30x^{2}=-60x
Subtract 30x^{2} from both sides.
-22x^{2}-12+10x=-60x
Combine 8x^{2} and -30x^{2} to get -22x^{2}.
-22x^{2}-12+10x+60x=0
Add 60x to both sides.
-22x^{2}-12+70x=0
Combine 10x and 60x to get 70x.
-22x^{2}+70x-12=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{-70±\sqrt{70^{2}-4\left(-22\right)\left(-12\right)}}{2\left(-22\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -22 for a, 70 for b, and -12 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-70±\sqrt{4900-4\left(-22\right)\left(-12\right)}}{2\left(-22\right)}
Square 70.
x=\frac{-70±\sqrt{4900+88\left(-12\right)}}{2\left(-22\right)}
Multiply -4 times -22.
x=\frac{-70±\sqrt{4900-1056}}{2\left(-22\right)}
Multiply 88 times -12.
x=\frac{-70±\sqrt{3844}}{2\left(-22\right)}
Add 4900 to -1056.
x=\frac{-70±62}{2\left(-22\right)}
Take the square root of 3844.
x=\frac{-70±62}{-44}
Multiply 2 times -22.
x=-\frac{8}{-44}
Now solve the equation x=\frac{-70±62}{-44} when ± is plus. Add -70 to 62.
x=\frac{2}{11}
Reduce the fraction \frac{-8}{-44} to lowest terms by extracting and canceling out 4.
x=-\frac{132}{-44}
Now solve the equation x=\frac{-70±62}{-44} when ± is minus. Subtract 62 from -70.
x=3
Divide -132 by -44.
x=\frac{2}{11} x=3
The equation is now solved.
\left(x^{2}-4\right)\times 3+x\left(x+2\right)\times 5=x\left(x-2\right)\times 30
Variable x cannot be equal to any of the values -2,0,2 since division by zero is not defined. Multiply both sides of the equation by x\left(x-2\right)\left(x+2\right), the least common multiple of x,x-2,x+2.
3x^{2}-12+x\left(x+2\right)\times 5=x\left(x-2\right)\times 30
Use the distributive property to multiply x^{2}-4 by 3.
3x^{2}-12+\left(x^{2}+2x\right)\times 5=x\left(x-2\right)\times 30
Use the distributive property to multiply x by x+2.
3x^{2}-12+5x^{2}+10x=x\left(x-2\right)\times 30
Use the distributive property to multiply x^{2}+2x by 5.
8x^{2}-12+10x=x\left(x-2\right)\times 30
Combine 3x^{2} and 5x^{2} to get 8x^{2}.
8x^{2}-12+10x=\left(x^{2}-2x\right)\times 30
Use the distributive property to multiply x by x-2.
8x^{2}-12+10x=30x^{2}-60x
Use the distributive property to multiply x^{2}-2x by 30.
8x^{2}-12+10x-30x^{2}=-60x
Subtract 30x^{2} from both sides.
-22x^{2}-12+10x=-60x
Combine 8x^{2} and -30x^{2} to get -22x^{2}.
-22x^{2}-12+10x+60x=0
Add 60x to both sides.
-22x^{2}-12+70x=0
Combine 10x and 60x to get 70x.
-22x^{2}+70x=12
Add 12 to both sides. Anything plus zero gives itself.
\frac{-22x^{2}+70x}{-22}=\frac{12}{-22}
Divide both sides by -22.
x^{2}+\frac{70}{-22}x=\frac{12}{-22}
Dividing by -22 undoes the multiplication by -22.
x^{2}-\frac{35}{11}x=\frac{12}{-22}
Reduce the fraction \frac{70}{-22} to lowest terms by extracting and canceling out 2.
x^{2}-\frac{35}{11}x=-\frac{6}{11}
Reduce the fraction \frac{12}{-22} to lowest terms by extracting and canceling out 2.
x^{2}-\frac{35}{11}x+\left(-\frac{35}{22}\right)^{2}=-\frac{6}{11}+\left(-\frac{35}{22}\right)^{2}
Divide -\frac{35}{11}, the coefficient of the x term, by 2 to get -\frac{35}{22}. Then add the square of -\frac{35}{22} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{35}{11}x+\frac{1225}{484}=-\frac{6}{11}+\frac{1225}{484}
Square -\frac{35}{22} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{35}{11}x+\frac{1225}{484}=\frac{961}{484}
Add -\frac{6}{11} to \frac{1225}{484} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{35}{22}\right)^{2}=\frac{961}{484}
Factor x^{2}-\frac{35}{11}x+\frac{1225}{484}. 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{35}{22}\right)^{2}}=\sqrt{\frac{961}{484}}
Take the square root of both sides of the equation.
x-\frac{35}{22}=\frac{31}{22} x-\frac{35}{22}=-\frac{31}{22}
Simplify.
x=3 x=\frac{2}{11}
Add \frac{35}{22} to both sides of the equation.
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