How do you factor the expression #k^2 + 11k + 28#?
#"Consider the factors of 28 which sum to + 11"#
#"the factors of + 28 which sum to + 11 are + 7 and + 4"#
Start by looking at your first term:
Now look at the signs of the second two terms: both are positive
From these observations, we know our factors will be:
because k times k will get us
Now, what two numbers will equal 11 when added together, and 28 when multiplied together?
The two numbers are 7 and 4.
So these complete our factors,