SOLUTION: using a phone card to make a long distance call costs a flat fee of $0.75 plus $0.25 per minute. What is an equation of the form y=mx +b for this situation, assuming y represents t

Algebra ->  Linear-equations -> SOLUTION: using a phone card to make a long distance call costs a flat fee of $0.75 plus $0.25 per minute. What is an equation of the form y=mx +b for this situation, assuming y represents t      Log On


   

Question 51822: using a phone card to make a long distance call costs a flat fee of $0.75 plus $0.25 per minute. What is an equation of the form y=mx +b for this situation, assuming y represents the total cost of calling for x minutes? How much does it cost to talk for 5 minutes?
Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
Total cost of calling x minutes: y
number of minutes called: x
rate per minute is the slope m: $0.25
flat fee without adding minutes is b: $0.75
Substitue these values into y=mx+b and you have:
y=.25x+.75
In order to find out the cost of talking 5 minutes, substitute 5 in for x:
y=.25(5)+.75
y=1.25+.75
y=2.00
It costs $2.00 to talk five minutes.