ПОМОГИТЕ РЕШИТЬ!!!!!! Очень прошу!!!

Решите задачу:

$\left \{ {{81^{2x-y}=9} \atop {(\sqrt7)^{3x+y}=49}} \right. \; \left \{ {{9^{4x-2y}=9^1} \atop {7^{\frac{3x+y}{2}}=7^2}} \right. \; \left \{ {{4x-2y=1} \atop {\frac{3x+y}{2}=2}} \right. \; \left \{ {{4x-2y=1} \atop {3x+y=4}} \right. \; \left \{ {{10x=9} \atop {3x+y=4} \right. \\\\ \left \{ {{x=0,9} \atop {y=1,3}} \right.$