3x(x-2)+4=2x2-1

Solution for 3x(x-2)+4=2x2-1 equation:

3x(x-2)+4=2x^2-1

We move all terms to the left:

3x(x-2)+4-(2x^2-1)=0

We multiply parentheses

3x^2-6x-(2x^2-1)+4=0

We get rid of parentheses

3x^2-2x^2-6x+1+4=0

We add all the numbers together, and all the variables

x^2-6x+5=0

a = 1; b = -6; c = +5;
Δ = b2-4ac
Δ = -62-4·1·5
Δ = 16
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{16}=4$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-6)-4}{2*1}=\frac{2}{2}
=1
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-6)+4}{2*1}=\frac{10}{2}
=5
$