c2=0.64

Solution for c2=0.64 equation:

c2=0.64

We move all terms to the left:

c2-(0.64)=0

We add all the numbers together, and all the variables

c^2-0.64=0

a = 1; b = 0; c = -0.64;
Δ = b2-4ac
Δ = 02-4·1·(-0.64)
Δ = 2.56
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$c_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$c_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$c_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-\sqrt{2.56}}{2*1}=\frac{0-\sqrt{2.56}}{2}
=-\frac{\sqrt{}}{2}
$
$c_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+\sqrt{2.56}}{2*1}=\frac{0+\sqrt{2.56}}{2}
=\frac{\sqrt{}}{2}
$