pucetrout966

Solve the following system of equations:

x-y=5

x²+y²=25

Solve the following system of equations. 

A train with cross-sectional area  is moving with speed  inside a long tunnel of cross-sectionalarea . Assume that almost all the air (density  ) in front of the train flows back between its sides and the walls of the tunnel. Also, the air flow with respect to the train is steady and laminar. Take the ambient pressure and that inside the train to be p0. If the pressure in the region between the sides of the train and the tunnel walls is p, then  . The value of N is ________.