Solve for x
x=\sqrt{7}\approx 2.645751311
x=-\sqrt{7}\approx -2.645751311
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x-3-\left(x+3\right)=3\left(x-3\right)\left(x+3\right)
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+3,x-3.
x-3-x-3=3\left(x-3\right)\left(x+3\right)
To find the opposite of x+3, find the opposite of each term.
-3-3=3\left(x-3\right)\left(x+3\right)
Combine x and -x to get 0.
-6=3\left(x-3\right)\left(x+3\right)
Subtract 3 from -3 to get -6.
-6=\left(3x-9\right)\left(x+3\right)
Use the distributive property to multiply 3 by x-3.
-6=3x^{2}-27
Use the distributive property to multiply 3x-9 by x+3 and combine like terms.
3x^{2}-27=-6
Swap sides so that all variable terms are on the left hand side.
3x^{2}=-6+27
Add 27 to both sides.
3x^{2}=21
Add -6 and 27 to get 21.
x^{2}=\frac{21}{3}
Divide both sides by 3.
x^{2}=7
Divide 21 by 3 to get 7.
x=\sqrt{7} x=-\sqrt{7}
Take the square root of both sides of the equation.
x-3-\left(x+3\right)=3\left(x-3\right)\left(x+3\right)
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+3,x-3.
x-3-x-3=3\left(x-3\right)\left(x+3\right)
To find the opposite of x+3, find the opposite of each term.
-3-3=3\left(x-3\right)\left(x+3\right)
Combine x and -x to get 0.
-6=3\left(x-3\right)\left(x+3\right)
Subtract 3 from -3 to get -6.
-6=\left(3x-9\right)\left(x+3\right)
Use the distributive property to multiply 3 by x-3.
-6=3x^{2}-27
Use the distributive property to multiply 3x-9 by x+3 and combine like terms.
3x^{2}-27=-6
Swap sides so that all variable terms are on the left hand side.
3x^{2}-27+6=0
Add 6 to both sides.
3x^{2}-21=0
Add -27 and 6 to get -21.
x=\frac{0±\sqrt{0^{2}-4\times 3\left(-21\right)}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, 0 for b, and -21 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 3\left(-21\right)}}{2\times 3}
Square 0.
x=\frac{0±\sqrt{-12\left(-21\right)}}{2\times 3}
Multiply -4 times 3.
x=\frac{0±\sqrt{252}}{2\times 3}
Multiply -12 times -21.
x=\frac{0±6\sqrt{7}}{2\times 3}
Take the square root of 252.
x=\frac{0±6\sqrt{7}}{6}
Multiply 2 times 3.
x=\sqrt{7}
Now solve the equation x=\frac{0±6\sqrt{7}}{6} when ± is plus.
x=-\sqrt{7}
Now solve the equation x=\frac{0±6\sqrt{7}}{6} when ± is minus.
x=\sqrt{7} x=-\sqrt{7}
The equation is now solved.
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