How do you factor a number?

There are many ways, but here is one.

Example:

A. x2 + 5x + 6

coefficients: 1, 5, 6

You have to find two numbers that the two ends multiply to get the sum of the middle coefficient in the order of ax2 + bx + c (read on to understand)

1 x 6 = 6

Find two numbers that multiply to 6, but add to 5

1 6 : 1 x 6 = 6, 1 + 6 = 7 X

2 3 : 2 x 3 = 6, 2 + 3 = 5 <---

So, the special numbers are 2 and 3.

Now, add them into this: (x+_)(x+_)

Both are positive, so it works! (x+2)(x+3)

Let's check.

(x+2)(x+3)

Use FOIL Method (first, outer, inner, last)

= x2 + 2x + 3x + 6

= x2 + 5x + 6

It works! Now, if you have trouble understanding, reread it a few times, and you'll get it in a blink!