Bus tickets cost $3 for an adult and $2 for a child. There are a adults and c children on a bus.
The total number of people on the bus is 52.
The total cost of the 52 tickets is $139.
Find the number of adults and the number of children on the bus.

Can some one me with these questions

Even if a person is in very good shape, applying to be a police officer requires commitment to fitness. applicants must pass a physical fitness test. in order to prepare for the test, janet purchases an activity tracker to court her steps. her goal is to walk 10,000 steps each day. she measures heard average step length to be 30 inches. play janet runs, her average steps length increases to 36 in. how many steps would she have to take to run 1 mile 50280 round to the nearest step

David leaves his house to go to school. he walks 200 meters west and 300 meters north. how far is david from his original starting point?