Factor 2m2 - m - 21

(2m-7) (m+3)

Step-by-step explanation:

hello:

2m² - m - 21

∆ = b²-4ac a=2 and b = - 1 and c = - 21

∆ = (-1) ²-4 (2) (-21) = 169 = 13²

m1 = (-b+√∆) / 2a = (1+13) 4 = 14/4 = 7/2

m2 = (-b-√∆) / 2a = (1-13) 4 = - 12/4 = - 3

the factorization is : a (m-m1) (m-m2)

2 (m-7/2) (m+3) = (2m-7) (m+3)