The ratio 21: 28 in simplest form is

4: 3
3: 4
3: 5

Astudent simplified a rational expression as shown.

What is the ratio of the change in y-values to the change in x-values for this function? a) 1: 13 b) 2: 5 c) 5: 2 d) 13: 1

If a and −a are numbers on the number line, which expression must give the distance between them? a) 0 b) a c) |2a| d) |a|