Answer:
B
Step-by-step explanation:
[tex]13x^{10}[/tex]
[tex]4x^{10}+9x^{10}[/tex]
[tex](4+9)x^{10}[/tex]
Because [tex]x^{10}[/tex] can be factored out from both terms, you just add 9 and 4 and keep the [tex]x^{10}[/tex].
