3.18x^2-4.2x+16=42

Solution for 3.18x^2-4.2x+16=42 equation:

3.18x^2-4.2x+16=42

We move all terms to the left:

3.18x^2-4.2x+16-(42)=0

We add all the numbers together, and all the variables

3.18x^2-4.2x-26=0

a = 3.18; b = -4.2; c = -26;
Δ = b2-4ac
Δ = -4.22-4·3.18·(-26)
Δ = 348.36
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{-(-4.2)-\sqrt{348.36}}{2*3.18}=\frac{4.2-\sqrt{348.36}}{6.36}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-4.2)+\sqrt{348.36}}{2*3.18}=\frac{4.2+\sqrt{348.36}}{6.36}
$