Solve for x
x=\sqrt{6}\approx 2.449489743
x=-\sqrt{6}\approx -2.449489743
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x^{2}-9=3\left(-1\right)
Consider \left(x+3\right)\left(x-3\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 3.
x^{2}-9=-3
Multiply 3 and -1 to get -3.
x^{2}=-3+9
Add 9 to both sides.
x^{2}=6
Add -3 and 9 to get 6.
x=\sqrt{6} x=-\sqrt{6}
Take the square root of both sides of the equation.
x^{2}-9=3\left(-1\right)
Consider \left(x+3\right)\left(x-3\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 3.
x^{2}-9=-3
Multiply 3 and -1 to get -3.
x^{2}-9+3=0
Add 3 to both sides.
x^{2}-6=0
Add -9 and 3 to get -6.
x=\frac{0±\sqrt{0^{2}-4\left(-6\right)}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, 0 for b, and -6 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-6\right)}}{2}
Square 0.
x=\frac{0±\sqrt{24}}{2}
Multiply -4 times -6.
x=\frac{0±2\sqrt{6}}{2}
Take the square root of 24.
x=\sqrt{6}
Now solve the equation x=\frac{0±2\sqrt{6}}{2} when ± is plus.
x=-\sqrt{6}
Now solve the equation x=\frac{0±2\sqrt{6}}{2} when ± is minus.
x=\sqrt{6} x=-\sqrt{6}
The equation is now solved.
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