Helen borrowed $8,000 from her grandfather to pay for college. Five years later, she paid him back the $8,000 and an interest of $1,200. What was the annual interest rate?

Aline has a slope of 1/4 and passes through point (0.4,-1/2). what is the value of the y-intercept?

Molly shared a spool of ribbon with 12 people. each person received 3 feet of ribbon. which equation can she use to find r, the number of feet of ribbon that her spool originally had?

Atruck can be rented from company a $50 a day plus $0.60 per mile. company b charges $20 a day plus $0.80 per mile to rent the same truck. find the number of miles in a day at which the rental costs for company a and company b are the same