Factorising a quadratic polynomial of the form,
ax2 + bx + c = 0
can be done in many depends depending on the values we have for a, b and c.
Some simple polynomial could be done simply by recognition. For example:
x2 + 4x + 3 = 0
In this scenario we would use the assumption that the factorisation is of the form:
(dx+e)(fx+g) = 0
and we would consider the values of d, e, f and g.
As the coefficient of the x2 term is 1, d and f would both be 1. Hence:
(x+e)(x+g) = 0
Now we need numbers for e and g such that:
e*g = 3 and,
e+g = 4
We find that e = 3 and g = 1 or visa versa.
Hence we can factorise
x2 + 4x + 3 = 0
to (x+3)(x+1) = 0