I really need help on this pls help

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 length of a rectangular piece of land is 92 yards more than three times its width. the perimeter is 760 yards. find its dimensions.

Ab and bc form a right angle at point b. if a= (-3,-1) and b= (4,4) what is the equation of bc?