-8 = 5x- x + 12 - 8 how to get x

How to do this , and can some one explain

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

Adele is five years older than timothy. in three years, timothy will be 2/3 of adele’s age. what is adele‘s current age?