Solve for x
x=3
x=-3
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3x-5x^{2}-3x=-45
Subtract 3x from both sides.
-5x^{2}=-45
Combine 3x and -3x to get 0.
x^{2}=\frac{-45}{-5}
Divide both sides by -5.
x^{2}=9
Divide -45 by -5 to get 9.
x=3 x=-3
Take the square root of both sides of the equation.
3x-5x^{2}-3x=-45
Subtract 3x from both sides.
-5x^{2}=-45
Combine 3x and -3x to get 0.
-5x^{2}+45=0
Add 45 to both sides.
x=\frac{0±\sqrt{0^{2}-4\left(-5\right)\times 45}}{2\left(-5\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -5 for a, 0 for b, and 45 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-5\right)\times 45}}{2\left(-5\right)}
Square 0.
x=\frac{0±\sqrt{20\times 45}}{2\left(-5\right)}
Multiply -4 times -5.
x=\frac{0±\sqrt{900}}{2\left(-5\right)}
Multiply 20 times 45.
x=\frac{0±30}{2\left(-5\right)}
Take the square root of 900.
x=\frac{0±30}{-10}
Multiply 2 times -5.
x=-3
Now solve the equation x=\frac{0±30}{-10} when ± is plus. Divide 30 by -10.
x=3
Now solve the equation x=\frac{0±30}{-10} when ± is minus. Divide -30 by -10.
x=-3 x=3
The equation is now solved.
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