Help how would I solve the quadratic equation by completing the square: 2y^2 - 5y - 12 = 0

the factors of 12 are: 1 and 12 - 2 and 6 - 3 and 4
Therefore;
2y^2 -5y -12 = 0
can be factored as
(2y + 3) * (y - 4) = 0
Therefore;
2y + 3 = 0 or y - 4 = 0
2y = -3 or y = 4
y = -3/2 or y = 4 < ==== Answer!
Check:
multiply terms (First, Outside, Inside, Last or FOIL)
2y^2 -8y + 3y -12 = o
2y^2 -5y -12 = 0
=================================
I hope this is helpful.

2(y^2-2.5y+(2.5/2)^2) - 2*(2.5/2)^2-12 = 0
(y-1.25)^2 = 6+1.25^2 = 7.5625
y = 1.25 +/- sqrt(7.5625)
y = 4 or -1.5

Can you just solve the equation? Factoring works... I can't remember how to complete a square sorry.