Answer:

Step-by-step explanation:
We are given that Ben has a cell phone plan that provides 200 free minutes each month for a flat rate of $39.
We are also told that For any minutes over 200, Ben is charged $0.35 per minute.
let x be the minutes used each month
So, if 
So, coat will be $39
If 
So, Ben is charged $0.35 per minute
So, when 
So, charge = 
So, the piecewise functions accurately represents charges based on Ben's cell phone :

Answer:
x=11/2
Step-by-step explanation:
Answer:
c. 5 - 17
Step-by-step explanation:
a. -15 - 3 = -18
b. -3 - (-9) = 6
c. 5 - 17 = -12
d. -6 - (-6) = 0
Actually you can't solve this. There is no solutions.