Answer:
C. y = 91
Step-by-step explanation:
you are given that x and y are proportional, this means that you can out them in a fraction
so when x is 8, y is 56, this can be written as 8/56
you are trying to find what y is when x is 3, so you can also put that in a proportion that is equal to the given fraction
so now we have 8/56 = 13/y
cross multiply 56 and 13, and 8 and x
you now have: 8y = 728
divide both sides by 8
you get y = 91
