Does anyone know of any great and easy ways to understand factoring quadriatic equations and polynomials?

Divide the steps to see what two numbers will equal the last term when multiplied and will also equal the middle term when they are added.
For example: x^2 + 5x + 6

__ • __ = 6
__ + __ = 5

3 times 2 will equal 6
3 plus 2 will equal five therefore the answer is (x +3)(x+2)

Sis less than or equal to 75 (bottom left)