Ответ:

x = 7, y = -3

Пошаговое объяснение:

4^(x+y) = 16 -> x+y = 4

4^(x+2y-1) = 1 -> x+2y-1 = 0 -> x + 2y = 1

x+y = 4 -> x = 4-y

4 - y + 2y = 1 -> y = -3 -> x = 7