2a(a-0.52)=8

Solution for 2a(a-0.52)=8 equation:

2a(a-0.52)=8

We move all terms to the left:

2a(a-0.52)-(8)=0

We multiply parentheses

2a^2-1.04a-8=0

a = 2; b = -1.04; c = -8;
Δ = b2-4ac
Δ = -1.042-4·2·(-8)
Δ = 65.0816
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$a_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(-1.04)-\sqrt{65.0816}}{2*2}=\frac{1.04-\sqrt{65.0816}}{4}
$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(-1.04)+\sqrt{65.0816}}{2*2}=\frac{1.04+\sqrt{65.0816}}{4}
$