k² + 13k + 30 = 0
This is a quadratic equation. Let's attempt solving it by factorization.
Coefficient of k² = 1, last term = 30
Multiply these two together 1*30 = 30
We think of two numbers that multiply to give 30 and add to give the middle term 13.
The two numbers are 3 and 10.
3*10 = 30, 3 + 10 = 13.
we replace the 13k with 3k + 10k
k² + 13k + 30 = 0
k² + 3k + 10k + 30 = 0
k(k + 3) + 10(k + 3) = 0
(k + 3)(k + 10) = 0
(k + 3) = 0 or (k + 10) = 0
k = 0 - 3 or k = 0 - 10
k = -3, or -10
I hope this helps.
