The graph seems to show the solution to be the point (50, 11), and, indeed, that point checks in both equations!
To use algebra to solve the linear system, make the problem easier to solve by eliminating fractions.
Multiply all terms in the first equation by 40 (the denominator in the coefficient of q):
Multiply all terms in the second equation by 50:
Add the two resulting equations.
Plug that back into either equation to get q=50.
To use algebra to solve the linear system, make the problem easier to solve by eliminating fractions.
Multiply all terms in the first equation by 40 (the denominator in the coefficient of q):
Multiply all terms in the second equation by 50:
Add the two resulting equations.
Plug that back into either equation to get q=50.