Aphone company offers two monthly plans. plan a costs $11 plus an additional $0.19 for each minute of calls. plan b costs $18 plus an additional $0.14 for each minute of calls. for what amount of calling do the two plans cost the same?

We call x the minutes to talk
+ Plan A costs $11 plus an additional $0.19 for each minute of calls, so we have the money for x minutes: 11+0.19x
+ Plan B costs $18 plus an additional $0.14 for each minute of calls. So we have the money for x minutes: 18+0.14x

We have solve this equation: 11+0.19x = 18+0.14x
or 0.19x-0.14x=18-11
and 0.05x= 7 we have x=7:0.05= 140
For 140 minutes of calling do the two plans cost the same