1.25x^2=320

Solution for 1.25x^2=320 equation:

1.25x^2=320

We move all terms to the left:

1.25x^2-(320)=0

a = 1.25; b = 0; c = -320;
Δ = b2-4ac
Δ = 02-4·1.25·(-320)
Δ = 1600
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{1600}=40$
$x_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-40}{2*1.25}=\frac{-40}{2.5}
=-16
$
$x_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+40}{2*1.25}=\frac{40}{2.5}
=16
$