Answer:
Step-by-step explanation:
A proportion is being directly related to something, meaning that there is just multiplication or division (just a coefficient in front of the x-coordinate, nothing more).
In a graph, a proportional graph is a graph that goes straight through the origin.
19.) Least to greatest:
Luxembourg
Singapore
Australia
Egypt
Brazil
This is the fundamental zero additive rule
x - 0 = x
which means that for the set of real numbers, there exist a number such that if added (or subtracted) from any other will not affect such number.