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(-5*x+3)*(-x+8)=0 equation

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Numerical solution:

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The solution

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(-5*x + 3)*(-x + 8) = 0
$$\left(3 - 5 x\right) \left(8 - x\right) = 0$$
Detail solution
Expand the expression in the equation
$$\left(3 - 5 x\right) \left(8 - x\right) = 0$$
We get the quadratic equation
$$5 x^{2} - 43 x + 24 = 0$$
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
$$a = 5$$
$$b = -43$$
$$c = 24$$
, then
D = b^2 - 4 * a * c = 

(-43)^2 - 4 * (5) * (24) = 1369

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

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

or
$$x_{1} = 8$$
$$x_{2} = \frac{3}{5}$$
Rapid solution [src]
x1 = 3/5
$$x_{1} = \frac{3}{5}$$
x2 = 8
$$x_{2} = 8$$
x2 = 8
Sum and product of roots [src]
sum
8 + 3/5
$$\frac{3}{5} + 8$$
=
43/5
$$\frac{43}{5}$$
product
8*3
---
 5 
$$\frac{3 \cdot 8}{5}$$
=
24/5
$$\frac{24}{5}$$
24/5
Numerical answer [src]
x1 = 8.0
x2 = 0.6
x2 = 0.6