What’s the answer for 2x+2?

What can you determine about the solutions of this system

What is the product? a-3/15a × 5/a-3

The party planning committee has to determine the number of tables needed for an upcoming event. if a square table can fit 8 people and a round table can fit 6 people, the equation 150 = 8x + 6y represents the number of each type of table needed for 150 people.