The revenue R in dollars received from selling x radios is R(x)=x(90-x). What number of radios sold will maximize revenue? What is the maximum revenue?

Question

anonymous · Answer

help me please

anonymous · Answer

multiply this out and get 
$$R(x)=90x-x^2$$
then the minimum will be at the vertex
first coordinate of the vertex is $-\frac{b}{2a}$ which in your case is $-\frac{90}{2\times (-1)}=45$

anonymous · Answer

oops i wrote "minimum" i meant "maximum" sorry

anonymous · Answer

45 is the maximum revenue right? so what would be the answer to the other question?

anonymous · Answer

??