A phone company offers two monthly plans. Plan A costs $18 plus an additional $0.10 for each minute of calls. Plan B costs $22 plus an additional $0.08 for each minute of calls.

Question

For what amount of calling do the two plans cost the same?

What is the cost when the two plans cost the same?

Answer 1

A
y = .10 x + 18

B
y = .08 x + 22

so
the same y when
.08 x + 22 = .10 x + 18
.02 x = 4
x = 4/.02 = 200 minutes
now go back and use either original equation to get y, the cost

Answer 2

A phone company offers two monthly plans. Plan A costs 18 plus an additional 0.08 for each minute of calls. Plan B has no initial fee but costs 0.12 for each minute of calls.

Answer 3

The first plan has no monthly fee but charges 0.14 for each minute of calls. The second plan has a 28$ monthly fee and charges an additional 0.09 for each minute of calls. For how many minutes of calls will the costs of the two plans be equal?