Need help solving

Nov 2012
3
0
la
[FONT=&quot]I was given Q = 400-2p, and I need to solve for P. The answer I arrived at is P = Q + 200. Is that correct?[/FONT]
 
Oct 2012
33
2
T'bilisi
[FONT="]I was given Q = 400-2p, and I need to solve for P. The answer I arrived at is P = Q + 200. Is that correct?[/FONT]
Hello scaliva21.
\(\displaystyle Q=400-2p\)

Since you want to solve for p, you have to isolate it, so you subtract 400 from both sides.

\(\displaystyle Q-400=-2p\)

and in order to continue isolation of p, you have to divide both sides by -2.

\(\displaystyle \frac{Q-400}{-2}=p\) -> \(\displaystyle p=\frac{Q}{-2}+\frac{-400}{-2}\) -> \(\displaystyle p=200-\frac{Q}{2}\)