Consider the trinomial x2 + 10x + 16.

Which pair of numbers has a product of ac and a sum of b?

2 and 52 and 84 and 4X 4 and 6

What is the factored form of the trinomial?

(x + 2) (x + 5) (x + 2) (x + 8) (x + 4) (x + 4) X (x + 4) (x + 6)

The coefficient of 10x and the last term 16 is what we'll focus on. Specifically just the numbers only (ignore the variable x for now).

Think of two numbers that both multiply to 16, and also add to 10. Those two numbers are 8 and 2 (in any order). You basically find this through trial and error.

8 + 2 = 10

8 * 2 = 16

So it factors to (x+8) (x+2). Since order of multiplication does not matter, this is the same as (x+2) (x+8)