Answer:
Plan A - 20x+40
Plan B - 30x
Step-by-step explanation:
x will determine the number of months.
For example, Plan A's equation
If I paid for one month, I should get $60.
20(1)+40 = 60
Now for three months, I should get $100. Because Plan A charges $20/month after a one time fee of $40 for the new phone.
20(3)+40 = 100
On the other hand, Plan B gives away a free phone, meaning no one-time fees. It only charges us $30/month. That's easy.
30(1) = $30
30(3) = $90
