Tolong yah. pleaseeee

4x – 3y = 15 |dikali 5
5x – 4y = 19 |dikali 4

20x – 15y = 75
20x – 16y = 76
y = -1

4x – 3y = 15
4x – 3(-1) = 15
4x = 15 -3
4x = 12
x = 3