Factorising Quadratics By Maths Grinds

So, in this video I’m looking at speed-running the factorization of $4x^2 – 19x + 12$. Again, normal rules apply, basically I can only do what an exam student can do (e.g. use an approved calculator etc.). I do pre-program into my calculator the quadratic formula, this is something you are allowed to do for the Leaving Cert! 🙂