Hi there, can someone please help me with my math homework. It’s only the blue highlighted sums I need. Please help I’ll really appreciate it.
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Answer:
(15)
[tex]-mn(2m+7n)[/tex]
(16)
[tex]x^{3}[/tex]
(17)
[tex]9x^{3}[/tex]
(18)
[tex]6x^{5}[/tex]
(19)
[tex]21m^{5} n^{3}[/tex]