Answer: 9 m + 7 n - 6 mn + 4 m
Explanation:
m + 3 n + 6 mn - 4 .... for this expression , it is already in its simplified form as we can not add any term together because they are not have the same variables.
9 m + 7 n - 6 mn + 4 ..... this also is already simplified
7 m - 9 n - 6 mn + 4 ..... the same thing with this
9 m + 7 n - 6 mn + 4 m .... this particular can still be further simplified because we have 9m and 4m having the same variable and we can therefore add them together , the simplified form of the expression will be
13m + 7n - 6mn