Question 281490
"Solve by elimination

How do I solve 4x-3y=39
               -3x-4y=23

I have worked this problem over and over please solve this for me."

 4x - 3y = 39 (multiply by 3)
-3x - 4y = 23 (multiply by 4)

 12x -  9y = 117
-12x - 16y = 92 (add 1st to 2nd)

 12x -  9y = 117
  0x - 25y = 209 (solve this one for y)

y = 209/(-25) = -209/25 = -8 9/25 = -8.36

plug in this y into 1st equation and solve for x
4x - 3(-8.36) = 39
4x + 25.08 = 39
4x = 13.92
x = 3.48

-3x-4y=23 (plug x and y into this one to check)
-3(3.48) - 4(-8.36) =? 23
-10.44 + 33.44 = 23 (works)