Question

Solve the following system by the comparison method.

2p + q = 1

9p + 3q + 3 = 0

What is the solution set?

{(-2, 5)}
{(2, -5)}
{(-2, -5)}

Answer 1

3p= -6
p=-2
q=5

Answer 2

Multiply first eq by 3 and subtract from the 2nd one

Answer 3

then what

Answer 4

Then you see that the q's cancel out and you get 3p = -6.
You get p=-2.
Then you plug p=-2 into any of the given equations to get q=5