Respuesta :

4x + 3y = 19     multiply this by 4
5x - 4y = 47       multiply this by 3:-

16x + 12y = 76..............(1)
15x - 12y =  141............(2)

Add (1) + (2);-

31x =   217
x = 7

Now plug  = 7 into the first equation:-

4(7) + 3y = 19
3y   = 19 - 28 = -9

t = -3

Solution is x = 7, y = -3.