@Confused student,
Quote:1) 3p = 2q
4p +q + 11 = 0
Use substitution. First try to figure out how many p's one q is worth.
If 2 q's are worth 3 p's. How much is one worth? Answer: q = 1.5p.
(That's called "solving for q.")
So where you see q in the second equation, you can substitute 1.5p:
4p + 1.5p + 11 = 0.
Combining like terms gives you 5.5p + 11 = 0.
Solving for p gives you p = -2.
Now put the value of p back into the first equation:
3(-2) = 2q.
Solving for q gives us: q = -3.
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Summary of overall strategy:
--Figure out what q is worth in terms of p, using the first equation.
--Rewrite the second equation, putting some multiple of p where q is.
--Solve the second equation for p.
--Figure out q.