3m^2-m-2=0 is of the form ax^2+bx+c
Find two values, j and k, which satisfy two conditions:
jk=ac=-6 and j+k=b=-1, so j and k must be 2 and -3
Now replace bx with jx and kx to get:
3m^2-3m+2m-2=0 now factor 1st and 2nd pair of terms
3m(m-1)+2(m-1)=0
(3m+2)(m-1)=0 so
m=-2/3 and 1