请问两道GWD数学

2.To be eligible for retirement benefits at the Omega Corporation, the sum of an employee’s age, in years, and the number of years of employment must be at least 70.  If x, where x < 70, is a certain employee’s age when hired and y is the minimum number of years of employment required for the employee to be eligible for retirement benefits, which of the following equations represents the relationship between x and y ?