Determine whether each statement qualifies as a definition. (a) y = f (x) is a...

Determine whether each statement qualifies as a definition.

(a) y = f (x) is a linear function if its graph is a straight line.

(b) y = f (x) is a quadratic function when it contains an term.

(c) A quadrilateral is a square when all its sides have equal length.

(d) A triangle is a right triangle if the sum of two of its interior angles is .

(e) Two lines are parallel when their slopes are the same number.

(f) A quadrilateral is a rectangle if all its interior angles are equal.