X+3y=18 3x +9y=12 parallel, perpendicular or coinciding

Aschool allots ? 1500 to spend on a trip to the theatre. theatre tickets have a regular cost of ? 55 each and are on offer for 1 5 off. a train ticket for the day will cost ? 12 each. if 2 teachers and the maximum number of students attend, how much money will the school have left over?

What is the slope of (0,32) and (100,212)

Compute the standard deviation of the following set of data to the nearest whole number. 10, 10, 15, 20, 25