Posted by natasha on Thursday, October 18, 2012 at 3:53pm.
4p + 2q = 8 and q = 2p +1 solve by substitution

algebra 2  Steve, Thursday, October 18, 2012 at 4:06pm
you have q = 2p+1
so, substitute into the other equation:
4p + 2(2p+1) = 8
4p + 4p + 2 = 8
8p = 6
p = 3/4
now you can get q.
be sure to check your answers in both equations, lest
a) you made a mistake
b) I made a mistake 
algebra 2  Joey, Thursday, October 18, 2012 at 4:10pm
4p + 2q = 8
q = 2p +1
Rearrange either so it aligns, I'll rearrange the bottom.
4p +2q = 8
2p  q = 8 (subtract 2p from both sides)
Pick one that simplifies easily I'll use the 4p one.
4p + 2q = 8
2q = 8  4p
q = 4 2p
Substitute q value for q in opposite equation
2p + (4  2p) = 1
2p + 4  2p = 1
4p = 3
p = 3/4
plug p in to find q 
algebra 2  Anonymous, Saturday, March 9, 2013 at 11:38am
Simplify: q – (7q + 1)