20=(0.0178x^2)+1.5x+16

Solution for 20=(0.0178x^2)+1.5x+16 equation:

20=(0.0178x^2)+1.5x+16

We move all terms to the left:

20-((0.0178x^2)+1.5x+16)=0


We calculate terms in parentheses: -((0.0178x^2)+1.5x+16), so:

(0.0178x^2)+1.5x+16

We add all the numbers together, and all the variables

1.5x+(0.0178x^2)+16

We get rid of parentheses

0.0178x^2+1.5x+16

Back to the equation:

-(0.0178x^2+1.5x+16)


We get rid of parentheses

-0.0178x^2-1.5x-16+20=0

We add all the numbers together, and all the variables

-0.0178x^2-1.5x+4=0

a = -0.0178; b = -1.5; c = +4;
Δ = b2-4ac
Δ = -1.52-4·(-0.0178)·4
Δ = 2.5348
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{-(-1.5)-\sqrt{2.5348}}{2*-0.0178}=\frac{1.5-\sqrt{2.5348}}{-0.0356}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1.5)+\sqrt{2.5348}}{2*-0.0178}=\frac{1.5+\sqrt{2.5348}}{-0.0356}
$