Answer:
a) P(x)=14x-224,000 and b) P(21,000)=70,000.
Step-by-step explanation:
a.) Use the formulas shown to write the company's profit function, P, from producing and selling x radios.
The company's profit is given by its revenue minus the production cost. Then, the profit function P(x) will be given by

b.) Find the company's profit if 21,000 radios are produced and sold
To obtain the company's profit we just need to substitute the value given (x=21,000) in the formula 1). Therefore,
.
-6 + x = -7
+6 +6 add 6 to both sides, 6's cancel out on the left.
________
x = -1, is the answer.
Hope this helps! Let me know if you have any other questions related to this problem. :)
It already is rounded to the nearest hundredth
Add them all up so it would equal 146.06