Answer:
For linear equations we use:
p=mx+b ------ (1)
Now we have the following coordinates:
(x1,p1)= (1000,280) and (x2, p2)=(5000,400)
First we need slope (m)
m=
=
Now we will plug the value of m in the first equation
=>
=> b = 250
Now plug into p=mx+b using only m=0.03 and b=250
When the unit price is $440, we can plug in 440 in for p;
=>
=>
=> x = 6333 refrigerators
The lowest price at which a refrigerator will be marketed, we can find this by plugging x = 0 in p=mx+b.
=> p = $250