х+у=7 х2-9у=7 Решите систему уравнения

x+y =7 2x - 9 = 7 x = 7 - y 2 (7 - y) - 9 = 7 14 - 2y - 9 = 7 -11y = - 7 y = 7/11 x = 7 - 7/11 = 6 4/11