Question 22404
The idea is to create the same number of "x's" or "y's" in both equations.
Then you subtract one equation from the other to eliminate that variable.
To get rid of the "x's" in your problem:
Multiply both sides of the 1st equation by 3 to get the following
24x + 15y = 18
Multiply both sides of the 2nd equation by 8 to get the following
24x - 16y = 80

Now, subtract the new 2nd equation from the new 1st equation to get
    31y= -62
      y=  -2
Substitute that value of y into either of the original equations to
solve for x.

Cheers,
Stan H.