Respuesta :

Simple, what you're basically doing is simplifying,

[tex] \frac{ 12x^{7} }{3x} [/tex]

well, you have 3x and you have [tex] 12x^{7} [/tex]

12/3=4

and you can "cancel" out an x, making your answer,

[tex] 4x^{6} [/tex].