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3x^2-75=0 equation

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Numerical solution:

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3*x  - 75 = 0
$$3 x^{2} - 75 = 0$$
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
$$a = 3$$
$$b = 0$$
$$c = -75$$
, then
D = b^2 - 4 * a * c = 

(0)^2 - 4 * (3) * (-75) = 900

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

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

or
$$x_{1} = 5$$
Simplify
$$x_{2} = -5$$
Simplify
Vieta's Theorem
rewrite the equation
$$3 x^{2} - 75 = 0$$
of
$$a x^{2} + b x + c = 0$$
as reduced quadratic equation
$$x^{2} + \frac{b x}{a} + \frac{c}{a} = 0$$
$$x^{2} - 25 = 0$$
$$p x + x^{2} + q = 0$$
where
$$p = \frac{b}{a}$$
$$p = 0$$
$$q = \frac{c}{a}$$
$$q = -25$$
Vieta Formulas
$$x_{1} + x_{2} = - p$$
$$x_{1} x_{2} = q$$
$$x_{1} + x_{2} = 0$$
$$x_{1} x_{2} = -25$$
Rapid solution [src]
x1 = -5
$$x_{1} = -5$$
x2 = 5
$$x_{2} = 5$$
Sum and product of roots [src]
sum
0 - 5 + 5
$$\left(-5 + 0\right) + 5$$
=
0
$$0$$
product
1*-5*5
$$1 \left(-5\right) 5$$
=
-25
$$-25$$
-25
Numerical answer [src]
x1 = 5.0
x2 = -5.0
x2 = -5.0