Answer:
You only have to sort (numbers with numbers and variables with variables) then do the operations (+/-).
Step-by-step explanation:
(A) The customer that owns a 3-kW system exports 120 kWh monthly to the grid will have the following bills for both companies:
For ZG&E that collects $3 per kWh on a monthly basis, the monthly bill will be
For Ready Edison that collects $0.06 per kWh exported energy monthly, the computation of bill will be
(B) The customer that owns a 5-kW system exports 300 kWh monthly to the grid will have the following bills for both companies:
For ZG&E that collects $3 per kWh on a monthly basis, the monthly bill will be
For Ready Edison that collects $0.06 per kWh exported energy monthly, the computation of bill will be
A binomial is going to have two terms. =)