Question 1194332
What is the money unit?  What problem solved is wanted?  For how many minute will the two plans be of equal cost?


Plan A:  {{{0.13x+9}}}
Plan B:  {{{0.08x+16}}}


Both plans become equal in cost being  {{{0.13x+9=0.08x+16}}}, and you can solve this for x number of minutes.