Movie theater a has a popcorn machine with 100 gallon capacity and sells 3 gallons of popcorn per our movie theater. B has a popcorn machine with 150 gallon capacity and sells 5 gallons of popcorn per hour right in an equation to show when the two popcorn machines will have the same amount of popcorn left use X as your variable.

100 - 3X = 150 - 5X