Answer:
[tex]x^{3} + 7x[/tex]
Step-by-step explanation:
cube of a number is the number multiplied by itself thrice.
This means:
x × x × x = [tex]x^{3}[/tex]
Seven times (multiply, ×) the number(x) means:
7 × x = [tex]7x[/tex]
We are to sum (add, +) both:
[tex]x^{3}[/tex] + [tex]7x[/tex]
Answer is [tex]x^{3}[/tex] + [tex]7x[/tex]