If the sum of twice a number and four is eighteen, what is that number?

Anew shopping mall is gaining in popularity. every day since it opened, the number of shoppers is 5% more than the number of shoppers the day before. the total number of shoppers over the first 10 days is 1258 how many shoppers were on the first day?

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.

The points (1, 7) and (0, 2) fall on a particular line. what is its equation in slope-intercept form?