СРОЧНО!!!! Системное уравнение

Решите задачу:

$\left \{ {{\frac{1}{5}u-\frac{1}{4}t=1} \atop {20u-26t=25}} \right. \rightarrow \left \{ {{-5t+4u=20\: |\: *(-5)} \atop {-26t+20u=25}} \right. \rightarrow \left \{ {{25-20u=-100} \atop {-26t+20u=25}} \right. \rightarrow \left \{ {{t=75} \atop {u=\frac{395}{4}}} \right. \\\\-t=-75\\\; \; \; t=75\\\\-5*75+4u=20\\\; \; \; u=\frac{395}{4} \\\\Otvet: (t,u)=(75, \frac{395}{4})$