1+ 10a-5a need on 6th grade algebra

According to modern science, earth is about 4.5 billion years old and written human history extends back about 10,000 years. suppose the entire history of earth is represented with a 10-meter-long timeline, with the birth of earth on one end and today at the other end.

Lines a and b are parallel. what is the value of x? -5 -10 -35 -55

Jack has to solve the problem 281-266.how would you tell him to solve the problem ? tell which strategy you would use ,and solve the problem.