0=x^2+3x-1.5

Solution for 0=x^2+3x-1.5 equation:

0=x^2+3x-1.5

We move all terms to the left:

0-(x^2+3x-1.5)=0

We add all the numbers together, and all the variables

-(x^2+3x-1.5)=0

We get rid of parentheses

-x^2-3x+1.5=0

We add all the numbers together, and all the variables

-1x^2-3x+1.5=0

a = -1; b = -3; c = +1.5;
Δ = b2-4ac
Δ = -32-4·(-1)·1.5
Δ = 15
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-3)-\sqrt{15}}{2*-1}=\frac{3-\sqrt{15}}{-2}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-3)+\sqrt{15}}{2*-1}=\frac{3+\sqrt{15}}{-2}
$