0=0.8x^2+10x-16

Solution for 0=0.8x^2+10x-16 equation:

0=0.8x^2+10x-16

We move all terms to the left:

0-(0.8x^2+10x-16)=0

We add all the numbers together, and all the variables

-(0.8x^2+10x-16)=0

We get rid of parentheses

-0.8x^2-10x+16=0

a = -0.8; b = -10; c = +16;
Δ = b2-4ac
Δ = -102-4·(-0.8)·16
Δ = 151.2
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{-(-10)-\sqrt{151.2}}{2*-0.8}=\frac{10-\sqrt{151.2}}{-1.6}
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-10)+\sqrt{151.2}}{2*-0.8}=\frac{10+\sqrt{151.2}}{-1.6}
$