1=0.625k^2

Solution for 1=0.625k^2 equation:

1=0.625k^2

We move all terms to the left:

1-(0.625k^2)=0

We get rid of parentheses

-0.625k^2+1=0

a = -0.625; b = 0; c = +1;
Δ = b2-4ac
Δ = 02-4·(-0.625)·1
Δ = 2.5
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$k_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$k_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$k_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-\sqrt{2.5}}{2*-0.625}=\frac{0-\sqrt{2.5}}{-1.25}
=-\frac{\sqrt{}}{-1.25}
$
$k_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+\sqrt{2.5}}{2*-0.625}=\frac{0+\sqrt{2.5}}{-1.25}
=\frac{\sqrt{}}{-1.25}
$