Simultaneous equation

Answer:
x = 5, y = 9.
Step-by-step explanation:
8^x / 2^y = 64
3^4x * (1/9)^(y -1) = 81
From the first equation
2^3x / 2^y = 2^6
2^(3x-y) = 2^6
So 3x - y = 6 ..........(1)
From the second equation:
3^4x * 9^(-(y-1)) = 3^4
3^4x * 3^2(-(y-1)) = 3^4
3^(4x+ 2(1 - y)) = 3^4
So 4x + 2(1 - y) = 4
4x - 2y = 2
2x - y = 1 .............(2)
Subtract: (1) - (2):
x = 5.
and 2(5) - y = 1
so y = 9.