A company manufactures two types of electronic devices: Device P and Device Q. Each Device P requires 3 hours of assembly and 2 hours of testing. Each Device Q requires 4 hours of assembly and 1 hour of testing. The company has a total of 240 assembly hours and 120 testing hours available per week. The graph shows the relationship between the number of Device P units, , and the number of Device Q units, , that can be produced based solely on the assembly hour constraint. Which equation represents this relationship?
