How do you factor #5t^2+37t+42=0#?

1 Answer
May 9, 2016

(5t + 7)(t + 6)

Explanation:

Use the new AC Method to factor trinomials (Socratic Search)
#y = 5t^2 + 37t + 42 =# 5(t + p)(t + q).
Converted trinomial: #y' = t^2 + 37t + 210 =# (t + p')(t + q').
p' and q' have same sign because ac > 0.
Factor pairs of (ac = 210) -->...(5, 42)(6, 35)(7, 30). This sum is (37 = b). Then, p' = 7 and q' = 30.
Back to original trinomial y --> #p = (p')/a = 7/5# and #q = (q')/a = 30/5 = 6#
Factored form: y = 5(t + 7/5)(x + 6) = (5t + 7)(t + 6).