What are the solutions to the system of equations?

Me find the measure to side c and the process to solve the problem you appreciate it : )

What is the perimeter of trapezoid jklm? + units 2 + + units 9 + units 9 + + units

Expresa commuter train leaves downtown sation and travels at a average speed of 55 miles per hour towards the north side sation, which is 50miles away. thirty minutes later, express commuter train #7 leaves north side and travels at a average speed of 35miles per hour towards downtown sation. at the moment the two trains pass each other, how far(in miles) is train #12 from the downtown sation and how long(in minutes) has the #12 train been traveling