2.5y2=40

Solution for 2.5y2=40 equation:

2.5y^2=40

We move all terms to the left:

2.5y^2-(40)=0

a = 2.5; b = 0; c = -40;
Δ = b2-4ac
Δ = 02-4·2.5·(-40)
Δ = 400
The delta value is higher than zero, so the equation has two solutions
We use following formulas to calculate our solutions:
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}$

$\sqrt{\Delta}=\sqrt{400}=20$
$y_{1}=\frac{-b-\sqrt{\Delta}}{2a}=\frac{-(0)-20}{2*2.5}=\frac{-20}{5}
=-4
$
$y_{2}=\frac{-b+\sqrt{\Delta}}{2a}=\frac{-(0)+20}{2*2.5}=\frac{20}{5}
=4
$