Solve for x
x=5
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30=\left(x+3\right)x-\left(x-3\right)x
Variable x cannot be equal to any of the values -3,3 since division by zero is not defined. Multiply both sides of the equation by \left(x-3\right)\left(x+3\right), the least common multiple of x^{2}-9,x-3,x+3.
30=x^{2}+3x-\left(x-3\right)x
Use the distributive property to multiply x+3 by x.
30=x^{2}+3x-\left(x^{2}-3x\right)
Use the distributive property to multiply x-3 by x.
30=x^{2}+3x-x^{2}+3x
To find the opposite of x^{2}-3x, find the opposite of each term.
30=3x+3x
Combine x^{2} and -x^{2} to get 0.
30=6x
Combine 3x and 3x to get 6x.
6x=30
Swap sides so that all variable terms are on the left hand side.
x=\frac{30}{6}
Divide both sides by 6.
x=5
Divide 30 by 6 to get 5.
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