PLEASE HELP ME! Solve: system by elimination form

1.
2x + y = 25
3y = 2x - 13

Adaycare center charges a $75 enrollment fee plus $100 per week. which of the following represents the cost of sending a child to daycare for 14 weeks?

Which function has the domain x> -11?

Acyclist bike x distance at 10 miles per hour .and returns over the same path at 8 miles per hour.what is the cyclist average rate for the round trip in miles per hour ?