# How do you factor #10m^2+7mn-12n^2#?

##### 1 Answer

May 31, 2015

I use the new AC Method to factor trinomials (Google, Yahoo Search)

y = 10m^2 + 7nm - 12n^2 = (m - p)(m - q).

Convert y to y' = m^2 + 7nm - 120n^2 = (m - p')(m - q')

Compose factor pairs of (a.c = -120n^2) -> (-2, 60)...(-8, 15). (Sum = 7)

Then p' = -8n and q' = 15n.

Then

Factored form:

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