The number of pieces of furniture a certain furniture store sold
since january can be modeled by the function n(t) = 10t +4
and the price per piece of furniture can be modeled by
p(t) = 2.5t2 – 12t + 65, where t is the number of months
since january.
according to this model, what is the total amount of revenue
generated by the furniture store's sales in december?

irrational, cannot

check above link.

graphically?   well, you graph them both, the solutions is where they both intersect each other, since there are two solutions, meaning they will meet twice, or namely the linear will run into the quadratic curve twice, and where they meet, those x,y coordinates are the solutions to the system.

i believe that the answer is

b. y-1=-2(x-4)

hope this !