SOLUTION: On a certain evening a 30 minute phone call costs $1.50. The next evening a 8 minute phone call costs $0.40. If the cost of an evening phone call is linear, find an equation to rep
Question 1108812: On a certain evening a 30 minute phone call costs $1.50. The next evening a 8 minute phone call costs $0.40. If the cost of an evening phone call is linear, find an equation to represent the cost of an evening phone call. Answer by josmiceli(19441) (Show Source):
You can put this solution on YOUR website! Plot time in minutes on the horizontal axis
Plot the cost for a call on the vertical axis
You are given the points:
( 30, 1.5 )
( 8, .4 )
Use the general point-slope formula:
-------------------------
check answer:
( 30, 1.5 )
( 8, .4 )
OK
