0=-0.012x^2+1.26x+45.5

Solution for 0=-0.012x^2+1.26x+45.5 equation:

0=-0.012x^2+1.26x+45.5

We move all terms to the left:

0-(-0.012x^2+1.26x+45.5)=0

We add all the numbers together, and all the variables

-(-0.012x^2+1.26x+45.5)=0

We get rid of parentheses

0.012x^2-1.26x-45.5=0

a = 0.012; b = -1.26; c = -45.5;
Δ = b2-4ac
Δ = -1.262-4·0.012·(-45.5)
Δ = 3.7716
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{-(-1.26)-\sqrt{3.7716}}{2*0.012}=\frac{1.26-\sqrt{3.7716}}{0.024}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1.26)+\sqrt{3.7716}}{2*0.012}=\frac{1.26+\sqrt{3.7716}}{0.024}
$