posted by Toby on .
Amir has $100 and is saving $5 per week to buy a new DVD player. Pete has $80 and ius saving $7 per week to buy the same DVD player. Which system of equations can be used to find w, the number of weeks it would take them to have m, the money needed to buy the DVD player?
Obviously for Amir m = 100 + 5w
and for Pete m = 80 + 7w
They buy the same DVD player ----> m = m
clearly 80 + 7w = 100 + 5w etc