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9x^2-45x=0 equation

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Numerical solution:

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The solution

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9*x  - 45*x = 0
$$9 x^{2} - 45 x = 0$$
Detail solution
This equation is of the form
a*x^2 + b*x + c = 0

A quadratic equation can be solved
using the discriminant.
The roots of the quadratic equation:
$$x_{1} = \frac{\sqrt{D} - b}{2 a}$$
$$x_{2} = \frac{- \sqrt{D} - b}{2 a}$$
where D = b^2 - 4*a*c - it is the discriminant.
Because
$$a = 9$$
$$b = -45$$
$$c = 0$$
, then
D = b^2 - 4 * a * c = 

(-45)^2 - 4 * (9) * (0) = 2025

Because D > 0, then the equation has two roots.
x1 = (-b + sqrt(D)) / (2*a)

x2 = (-b - sqrt(D)) / (2*a)

or
$$x_{1} = 5$$
$$x_{2} = 0$$
Vieta's Theorem
rewrite the equation
$$9 x^{2} - 45 x = 0$$
of
$$a x^{2} + b x + c = 0$$
as reduced quadratic equation
$$x^{2} + \frac{b x}{a} + \frac{c}{a} = 0$$
$$x^{2} - 5 x = 0$$
$$p x + q + x^{2} = 0$$
where
$$p = \frac{b}{a}$$
$$p = -5$$
$$q = \frac{c}{a}$$
$$q = 0$$
Vieta Formulas
$$x_{1} + x_{2} = - p$$
$$x_{1} x_{2} = q$$
$$x_{1} + x_{2} = 5$$
$$x_{1} x_{2} = 0$$
Rapid solution [src]
x1 = 0
$$x_{1} = 0$$
x2 = 5
$$x_{2} = 5$$
x2 = 5
Sum and product of roots [src]
sum
5
$$5$$
=
5
$$5$$
product
0*5
$$0 \cdot 5$$
=
0
$$0$$
0
Numerical answer [src]
x1 = 5.0
x2 = 0.0
x2 = 0.0