Question 175242
you look for factors of 45 that will add up to 18.
45 = 9*5 the sum of which is 9 + 5 = 14 (no good)
45 = 3*15 the sum of which is 3 + 15 = 18 (good)
your factors are:
(z+15) * (z+3)
you multiply these together to get:
z^2 + 18z + 45
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