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1+3x-10x^2=0

1+3x-10x^2=0 equation

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Numerical solution:

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The solution

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1 + 3*x - 10*x  = 0
$$- 10 x^{2} + \left(3 x + 1\right) = 0$$
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
$$a = -10$$
$$b = 3$$
$$c = 1$$
, then
D = b^2 - 4 * a * c = 

(3)^2 - 4 * (-10) * (1) = 49

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

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

or
$$x_{1} = - \frac{1}{5}$$
$$x_{2} = \frac{1}{2}$$
Vieta's Theorem
rewrite the equation
$$- 10 x^{2} + \left(3 x + 1\right) = 0$$
of
$$a x^{2} + b x + c = 0$$
as reduced quadratic equation
$$x^{2} + \frac{b x}{a} + \frac{c}{a} = 0$$
$$x^{2} - \frac{3 x}{10} - \frac{1}{10} = 0$$
$$p x + q + x^{2} = 0$$
where
$$p = \frac{b}{a}$$
$$p = - \frac{3}{10}$$
$$q = \frac{c}{a}$$
$$q = - \frac{1}{10}$$
Vieta Formulas
$$x_{1} + x_{2} = - p$$
$$x_{1} x_{2} = q$$
$$x_{1} + x_{2} = \frac{3}{10}$$
$$x_{1} x_{2} = - \frac{1}{10}$$
The graph
Rapid solution [src]
x1 = -1/5
$$x_{1} = - \frac{1}{5}$$
x2 = 1/2
$$x_{2} = \frac{1}{2}$$
x2 = 1/2
Sum and product of roots [src]
sum
-1/5 + 1/2
$$- \frac{1}{5} + \frac{1}{2}$$
=
3/10
$$\frac{3}{10}$$
product
-1 
---
5*2
$$- \frac{1}{10}$$
=
-1/10
$$- \frac{1}{10}$$
-1/10
Numerical answer [src]
x1 = 0.5
x2 = -0.2
x2 = -0.2
The graph
1+3x-10x^2=0 equation