I need help with this problem I solved the last 2 questions but I am not sure how to do the first question.

Question

An important application of systems of equations arises in connection with supply and demand. As the price of a product increases, the demand for that product decreases. However, at higher prices, suppliers are willing to produce greater quantities of the product. Suppose a chain of electronics stores sells hand-held color televisions. The weekly demand and supply models are given as follows

Demand Model: N=-6p+2520

Supply Model: N=2.4p

where N is the number of televisions sold each week and at price p. (Note: Answer with the appropriate units.)\

a) How many hand-held color televisions can be sold at $ 320 per television?

Answer 1

-6p+2520=2.4p

8.4p=2520

p=2520/8.4=$300

2520-6(300)=720 sets

at $320, there is a surplus of 168 unsold sets, and pice will fall to the equilibrium price = $300

suppliers will have =768 ready to sell

but only 2520-6(320)=600 sets will be sold