Verified answer

Ответ:

u=15

t=12

Объяснение:

[tex]\left \{ {{\frac{u+t}{9}-\frac{u-t}{3} =2} \atop {\frac{2u-t}{6}-\frac{3u+2t}{3} =-20}} \right. \\\\\left \{ {{u+t-3u+3t=18} \atop {2u-t-6u-4t=-120}} \right. \\\\\left \{ {{4t-2u=18} \atop {-4u-5t=-120}} \right. |^{2} _{-1}\\\\\left \{ {{8t-4u=36} \atop {4u+5t=120}} \right. |+\\\\13t=156\\t=156/13\\t=12\\\\4*12-2u=18\\-2u=18-48\\-2u=-30\\u=30/2\\u=15[/tex]