Based on the context provided and typical terminology used in geometry and graphing, the responses to fill in the blanks would likely be as follows:
a. Triangles ABC and CDE are called similar.
b. The slope of line AE can be written as change in y/change in x.
c. This is a proportional relationship.
So, the final responses are:
a. similar
b. change in y/change in x
c. proportional