Math  Word Problem
posted by Lynn on .
Word problems confuse me >_>
You are choosing between two longdistance telephone companies. Company A charges $.09 per minute plus $4 monthly fee. Company B charges $.11 per minute with no monthly fee.
X = number of minutes you call long distance
y = total cost of long distance phone service.
How am I suppose to write two equations representing the cost of each company's service for one month?

Just take each sentence and figure out what is says algebraically.
Company A: for x minutes, the charge is 9x + 400 cents
Company B: for x minutes, the charge is 11x with no extra fee.
So, which company is cheaper? That obviously will depend on the number of minutes you use.
So, when will A charge more than B?
9x + 400 > 11x
400 > 2x
200 > x
So, if you use less than 200 minutes, A charges more.
At 200 minutes,
9*200 + 400 = 1800+400 = $22.00
11*200 = $22.00
If using more than 200 minutes, A only charges an extra 4 cents/min, while B charges 11 cents/min, so A will be cheaper. 
The cell phone bill has a base fee of $30 per month plus twenty cents per minute.