If sinθ/secθ =1/2, find sinθ+secθ/sinθ-secθ

Tom is the deli manager at a grocery store. he needs to schedule employee to staff the deli department for no more that 260 person-hours per week. tom has one part-time employee who works 20 person-hours per week. each full-time employee works 40 person-hours per week. write and inequality to determine n, the number of full-time employees tom may schedule, so that his employees work on more than 260 person-hours per week. graph the solution set to this inequality.

Me find the answer and explain the process to find the answer of the problem appreciate it : )

X+ 4y − z = −14 5x + 6y + 3z = 4 −2x + 7y + 2z = −17