# Math Help - Need help

1. ## Need help

How do I solve the followinf equation using the elmination method?

p = 28 +q
3p = -9q+120

2. Originally Posted by mathdummy22
How do I solve the followinf equation using the elmination method?

p = 28 +q
3p = -9q+120
First rewrite it as

$\begin{array}{rcrcr}p&-&q&=&28\\3p&+&9q&=&120\end{array}$

I noticed that if you divide the second equation through by 3, you end up with this system:

$\begin{array}{rcrcr}p&-&q&=&28\\p&+&3q&=&40\end{array}$

I would like to eliminate p. Thus, multiply the first equation by -1 and then add the equations together:

$\begin{array}{rcrcr}-p&+&q&=&-28\\p&+&3q&=&40\end{array}\implies 4q=12\implies \color{red}\boxed{q=3}$

Can you find p?

--Chris

3. will p = 31 ?