Should I accept the job offers before having the results for my grad schoold admissions?
Are the jobs and Master's programs in the same city? Many graduate programs are designed around the idea that many participants have 9-5 jobs. It may be possible to do work towards a Master's while employed. If you think that would be too difficult,  you might be able to ask your employer whether you can drop down to part-time status. Another option is to look into delaying the start of the Master's program for a semester or two, so you're not leaving the job right after starting.