write the slope intercept form of the equation of the line through the given points (-5,0) and (-5,5)

Twice the sum of a number and 4 is equal to three times the difference of the number and 7. find the number.

Four airplanes carrying a total of 400 passengersarrive at the detroit airport. the airplanes carry, respectively,50, 80, 110, and 160 passengers.a) one of the 400 passengers is selected uniformly at random.let x denote the number of passengers that were on theairplane carrying the randomly selected passenger. find var(x)for x as given in the problemb) one of the 4 airplane drivers is also selected uniformly atrandom. let y denote the number of passengers on the chosen driver’s airplane. find var(y) for y as given in the problem

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.