The vertex of the parabola is at (5,3) and its focal length is 8/4 = 2.
Since it opens to the right, the directrix will be a vertical line 2 units to the left of the vertex, so its equation will be x=(5-2), or x=3
One value: would be a single valued function, or just one answer.
Real numbers would be: natural numbers, whole numbers, integers, rational numbers (fractions and repeating or terminating decimals), and irrational numbers.
No solution: there is no answer to the question.
