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\left(x+3\right)\left(3-x\right)=5
Variable x cannot be equal to -3 since division by zero is not defined. Multiply both sides of the equation by 5\left(x+3\right), the least common multiple of 5,x+3.
9-x^{2}=5
Consider \left(x+3\right)\left(3-x\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}=5-9
Subtract 9 from both sides.
-x^{2}=-4
Subtract 9 from 5 to get -4.
x^{2}=\frac{-4}{-1}
Divide both sides by -1.
x^{2}=4
Fraction \frac{-4}{-1} can be simplified to 4 by removing the negative sign from both the numerator and the denominator.
x=2 x=-2
Take the square root of both sides of the equation.
\left(x+3\right)\left(3-x\right)=5
Variable x cannot be equal to -3 since division by zero is not defined. Multiply both sides of the equation by 5\left(x+3\right), the least common multiple of 5,x+3.
9-x^{2}=5
Consider \left(x+3\right)\left(3-x\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.
9-x^{2}-5=0
Subtract 5 from both sides.
4-x^{2}=0
Subtract 5 from 9 to get 4.
-x^{2}+4=0
Quadratic equations like this one, with an x^{2} term but no x term, can still be solved using the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}, once they are put in standard form: ax^{2}+bx+c=0.
x=\frac{0±\sqrt{0^{2}-4\left(-1\right)\times 4}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 for a, 0 for b, and 4 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-1\right)\times 4}}{2\left(-1\right)}
Square 0.
x=\frac{0±\sqrt{4\times 4}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{0±\sqrt{16}}{2\left(-1\right)}
Multiply 4 times 4.
x=\frac{0±4}{2\left(-1\right)}
Take the square root of 16.
x=\frac{0±4}{-2}
Multiply 2 times -1.
x=-2
Now solve the equation x=\frac{0±4}{-2} when ± is plus. Divide 4 by -2.
x=2
Now solve the equation x=\frac{0±4}{-2} when ± is minus. Divide -4 by -2.
x=-2 x=2
The equation is now solved.