When completing the square, does the value of a always need to be one?

Yeah, mostly is has to be negative, but in some cases a is greater than 1 than we do some other operations.

a line is an defined derm because it

a)contains an infinite number of points b) can be used to create other geometric shapes c)describes something that does not have width or depth d) is a term that does not have a formal definition. a line is an undefined term because it: contains an infinite number of points.