Respuesta :
7x-4y=5.... ..... --> y = (5-7x)/(-4)
9x+8y = 13 ... --> y = (13-9x)/8
Igualacion:
(5-7x)/(-4) = (13-9x)/8
40 - 56x = -52 + 36x
92 = 92 x
x = 1
y = (13 - 9(1) ) / 8
y = 4 / 8
y = 1/2
7x-4y=5 --> 7(1) - 4(1/2) = 5
9x+8y = 13 --> 9(1) + 8 (1/2) = 13