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30*x^2+15,97*x-1597=0 equation

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Numerical solution:

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The solution

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    2   1597*x           
30*x  + ------ - 1597 = 0
         100             
$$\left(30 x^{2} + \frac{1597 x}{100}\right) - 1597 = 0$$
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
$$a = 30$$
$$b = \frac{1597}{100}$$
$$c = -1597$$
, then
D = b^2 - 4 * a * c = 

(1597/100)^2 - 4 * (30) * (-1597) = 1918950409/10000

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

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

or
$$x_{1} = - \frac{1597}{6000} + \frac{\sqrt{1918950409}}{6000}$$
$$x_{2} = - \frac{\sqrt{1918950409}}{6000} - \frac{1597}{6000}$$
Vieta's Theorem
rewrite the equation
$$\left(30 x^{2} + \frac{1597 x}{100}\right) - 1597 = 0$$
of
$$a x^{2} + b x + c = 0$$
as reduced quadratic equation
$$x^{2} + \frac{b x}{a} + \frac{c}{a} = 0$$
$$x^{2} + \frac{1597 x}{3000} - \frac{1597}{30} = 0$$
$$p x + q + x^{2} = 0$$
where
$$p = \frac{b}{a}$$
$$p = \frac{1597}{3000}$$
$$q = \frac{c}{a}$$
$$q = - \frac{1597}{30}$$
Vieta Formulas
$$x_{1} + x_{2} = - p$$
$$x_{1} x_{2} = q$$
$$x_{1} + x_{2} = - \frac{1597}{3000}$$
$$x_{1} x_{2} = - \frac{1597}{30}$$
Rapid solution [src]
                ____________
       1597   \/ 1918950409 
x1 = - ---- + --------------
       6000        6000     
$$x_{1} = - \frac{1597}{6000} + \frac{\sqrt{1918950409}}{6000}$$
                ____________
       1597   \/ 1918950409 
x2 = - ---- - --------------
       6000        6000     
$$x_{2} = - \frac{\sqrt{1918950409}}{6000} - \frac{1597}{6000}$$
x2 = -sqrt(1918950409)/6000 - 1597/6000
Sum and product of roots [src]
sum
           ____________              ____________
  1597   \/ 1918950409      1597   \/ 1918950409 
- ---- + -------------- + - ---- - --------------
  6000        6000          6000        6000     
$$\left(- \frac{\sqrt{1918950409}}{6000} - \frac{1597}{6000}\right) + \left(- \frac{1597}{6000} + \frac{\sqrt{1918950409}}{6000}\right)$$
=
-1597 
------
 3000 
$$- \frac{1597}{3000}$$
product
/           ____________\ /           ____________\
|  1597   \/ 1918950409 | |  1597   \/ 1918950409 |
|- ---- + --------------|*|- ---- - --------------|
\  6000        6000     / \  6000        6000     /
$$\left(- \frac{1597}{6000} + \frac{\sqrt{1918950409}}{6000}\right) \left(- \frac{\sqrt{1918950409}}{6000} - \frac{1597}{6000}\right)$$
=
-1597 
------
  30  
$$- \frac{1597}{30}$$
-1597/30
Numerical answer [src]
x1 = -7.5671376998771
x2 = 7.03480436654376
x2 = 7.03480436654376