During a certain 25-year period, the consumer price index (CPI) increased by 99%, but during the next 25-year period, it increased by only 1%. Which of these conditions must have existed during the second 25-year period?

7x+8y=-18, 4x-9y=-3 solve the system of equations

Which equation represents a line that passes through the point (9, -4) and has a slope of 3/5?

Dana wants to identify the favorite professional baseball team of people in her community. she stands outside a local sporting goods store and asks every other person who enters, "what is your favorite professional baseball team? " will the results of her survey be valid? explain.