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-x^2+2*x+3=0

-x^2+2*x+3=0 equation

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Numerical solution:

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The solution

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

(2)^2 - 4 * (-1) * (3) = 16

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

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

or
$$x_{1} = -1$$
$$x_{2} = 3$$
Vieta's Theorem
rewrite the equation
$$\left(- x^{2} + 2 x\right) + 3 = 0$$
of
$$a x^{2} + b x + c = 0$$
as reduced quadratic equation
$$x^{2} + \frac{b x}{a} + \frac{c}{a} = 0$$
$$x^{2} - 2 x - 3 = 0$$
$$p x + q + x^{2} = 0$$
where
$$p = \frac{b}{a}$$
$$p = -2$$
$$q = \frac{c}{a}$$
$$q = -3$$
Vieta Formulas
$$x_{1} + x_{2} = - p$$
$$x_{1} x_{2} = q$$
$$x_{1} + x_{2} = 2$$
$$x_{1} x_{2} = -3$$
The graph
Rapid solution [src]
x1 = -1
$$x_{1} = -1$$
x2 = 3
$$x_{2} = 3$$
x2 = 3
Sum and product of roots [src]
sum
-1 + 3
$$-1 + 3$$
=
2
$$2$$
product
-3
$$- 3$$
=
-3
$$-3$$
-3
Numerical answer [src]
x1 = 3.0
x2 = -1.0
x2 = -1.0
The graph
-x^2+2*x+3=0 equation