+2729 Fill in the blank with a constant, so that the resulting expression can be factored as the product of two linear expressions:
2mn - 21m + 6n + mn - 9m + ___
+410 3mn−30m+6n+c
3m(n−10)+6n+c
3m(n−10)+6(n−10)+60+c
(3m+6)(n−10)+60+c
c+60=0
c=−60
The constant is -60.
+410 3mn−30m+6n+c
3m(n−10)+6n+c
3m(n−10)+6(n−10)+60+c
(3m+6)(n−10)+60+c
c+60=0
c=−60
The constant is -60.
