The map is a flat schematic of some actual distance, on a map, the distance form point A to point B may well be 10 units say, however, in actuality, if you go and walk from point A to point B, you'd notice that, first off is not a straight line most of the time, and also it may have a slanted or sloped section, and the map is not including that slope or hill, whilst you do have to walk it.
so, adding all the twists and curves along the way and any bumps or slopes, is really not exactly 10 units from A to B.
Check the picture below.
now, we know the directrix is at y = 1, and the focus point is at 1,3, well, notice the picture, the distance between those fellows is just 2 units.
the vertex is half-way between those fellows, therefore, the vertex will be at 1,2.
the distance "p", from the vertex to either the directrix or focus, is really just 1 unit. Since the focus point is above the directrix, is a vertical parabola, and it opens upwards, like in the picture, and since it opens up, the "p" value is positive, or +1.
Step-by-step explanation:
itulog mo nalang yan, walang ganun lods
-1 as a negative would = X
The trapezoid,segment is false