Question

How to do quadritic equations faster​

Answer 1

Answer:

The best way, I call it middle-split.

Taking your equation under the spotlight

x2+3x−4=0

Think of 2 numbers p,q such that p+q=3 and pq=−4

That yields 4,−1 as one of the pair.

So, we split the equation from the middle such that x2−x+4x−4=0

Now, it is easy to factorize. x(x−1)+4(x−1)=0

(x+4)(x−1)=0

So, either x=−4 or x=1

Quite often this trick will work. But, always emphasis that you use the quadratic formula, which removes the "guess-work" involved, and relies completely on computation.

x=−b±b2−4ac−−−−−−−√2a