Question

Решите систему уравнений
Х+у=8
х-2у=11

Answer 1

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Answer 2

x=8-y; 8-y-2y=11; -y-2y=11-8; -3y=3; y=3/(-3)= -1. x=8-(-1)=8+1=9. Ответ: (9:-1).