Andrew was calling family in Italy. The formula C = 0.23m + 0.89, where C represents cost, in dollars, and m represents
minutes, can be used to determine the cost of a phone call to
Italy.
What if Andrew talked for 1 hours.
How much would his phone call
cost?

This works out to $14.69.

Step-by-step explanation:

C = 0.23m +  0.89 is measured in dollars.  $0.89 is the up-front cost, which happens to be the y-intercept.  $0.23/min is the unit rate:  cost per minute.

Recalling that 1 hour = 60 minutes,

write C(60 min) = $0.89 + ($0.23/min)(60 min)

This works out to $14.69.

c

step-by-step explanation:

c

tip $2.90

total $17.40