a2=1.21

Solution for a2=1.21 equation:

a2=1.21

We move all terms to the left:

a2-(1.21)=0

We add all the numbers together, and all the variables

a^2-1.21=0

a = 1; b = 0; c = -1.21;
Δ = b2-4ac
Δ = 02-4·1·(-1.21)
Δ = 4.84
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{-(0)-\sqrt{4.84}}{2*1}=\frac{0-\sqrt{4.84}}{2}
=-\frac{\sqrt{}}{2}
$
$a_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+\sqrt{4.84}}{2*1}=\frac{0+\sqrt{4.84}}{2}
=\frac{\sqrt{}}{2}
$