Y1=0.0058x^2-0.67x+15.2

Solution for Y1=0.0058x^2-0.67x+15.2 equation:

1=0.0058Y^2-0.67Y+15.2

We move all terms to the left:

1-(0.0058Y^2-0.67Y+15.2)=0

We get rid of parentheses

-0.0058Y^2+0.67Y-15.2+1=0

We add all the numbers together, and all the variables

-0.0058Y^2+0.67Y-14.2=0

a = -0.0058; b = 0.67; c = -14.2;
Δ = b2-4ac
Δ = 0.672-4·(-0.0058)·(-14.2)
Δ = 0.11946
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$Y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$Y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$Y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0.67)-\sqrt{0.11946}}{2*-0.0058}=\frac{-0.67-\sqrt{0.11946}}{-0.0116}
$
$Y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0.67)+\sqrt{0.11946}}{2*-0.0058}=\frac{-0.67+\sqrt{0.11946}}{-0.0116}
$