8. D: The longest sides of the quadrilaterals are 30 and 10. That is a 30 : 10 ratio, which simplifies to 3 : 1, or 3/1. It's not 1 : 3 because it is the ratio between the large (comes first) to the small (comes second) figure.
9. B: x corresponds to 26, and from the previous problem, we figured out that the sides of the larger figure are 3 times larger than the corresponding one on the smaller one. So x is 1/3 the length of 26, which is 26/3.