3x - y = 23, (1)
= 4. (2)
Multiply equation (2) by 12 (both sides) to rid off the denominators. You will get
3x - y = 23, (1')
4x + 3y = 48. (2')
To eliminate "y", multiply the equation (1') by 3 (both sides). You will get
9x - 3y = 69, (1'')
4x + 3y = 48. (2'')
Now add equations (1'') and (2'') (both sides). You will get
9x + 4x = 117 ====> 13x = 117 ====> x = = 9.
Now y = 3x - 23 = 3*9 - 23 = 27 - 23 = 4.
Answer. x = 9, y = 4.