application or intradermal injection of a substance to the skin to test the body's reaction to it. Such a test detects an animal's sensitivity to such allergens as dust and pollen, or to preparations of microorganisms believed to be the cause of a disorder.
A direct relationship graph is a graph where one variable either increases or decreases along with the other. The general equation for a direct relationship graph is y = mx + b, where y denotes the...
The graph of a direct relationship is very distinctive. If a graph is a straight line with a positive slope AND goes through the point (0, 0), then the relationship is direct. Definition: A quantity y is directly proportional to a quantity x if y = kx for some k > 0. k is called the constant of proportionality and this can be represented through a graph as shown below: Often just the term proportional is used to mean directly proportional.