Is y= 2X +7 a function

To complete your spring schedule, you must add calculus and physics. at 9: 30, there are three calculus sections and two physics sections; while at 11: 30, there are two calculus sections and three physics sections. how many ways can you complete your schedule if your only open periods are 9: 30 and 11: 30?

The system of equations graphed below has how many solutions?

With these: 18/36 = 1/? missing number change 1 5/8 to improper fraction. change 19/5 to a mixed number.