Yes because volume has 3 dimensions, hence the power of 3
Answer:
I will try to do it
Step-by-step explanation:
Given :
AT&T charges $350 to get a plan with them, plus $60 per month.
T-Mobile charges a $275 initial fee, plus $80 per month.
To Find :
Write an equation or inequality that can be used to determine the number of months it would take for T-Mobile to cost the same or more than AT&T.
Solution :
Money-time relation of plan AT&T :

Money-time relation of plan T-Mobile :

( Here, x and y are number of months )
Let, after t months would take for T-Mobile to cost the same or more than AT&T.
So, 

Hence, this is the required solution.
<span>(x - 8) (x + 8)
= x^2 - 8x + 8x -64
= x^2 - 64</span>