Eight out of 64 workstations in an office are going to be replaced. The cost of replacing all 64 workstations would be $10,200. Additionally, four workstations will receive a computer upgrade. The cost of a computer upgrade for all 64 workstations would be $6,300. Two of the workstations that are being upgraded are eligible for a used equipment return. If all 64 workstations were eligible for an equipment return, the office would receive a total of $1,050. What would be this equation