Answer:
Use the distributive property to distribute m and 3
[tex]m^{3}[/tex] + 4[tex]m^{2}[/tex] +7m + 3[tex]m^{2}[/tex] + 12m + 21
once you distribute, combine like terms
this is your final answer once you combine:
[tex]m^{3}[/tex] + 7[tex]m^{2}[/tex] + 19m + 21
