Q&A for How to Draw a Parabolic Curve (a Curve with Straight Lines)

Use a compass to draw a circle, as shown in the example. This can be done on any type of paper.

Use the edge of a piece of paper or anything straight, or go freehand. Visually guess the distances if you don't have graph paper.

Technically the center of a parabola is undefined since a parabola exists infinitely.

It's just 3 squares at a slanted angle. Just make the same marks on the sides like you would do on a single square for all three parts and do the curves normally.

In the drawing, there are 10 units in X and 10 in Y. The focal point is where the line is equadistant from the directrix, so it must be at X-10, Y=10.

It is at 6 X 6. It must be at the height where the edge is at 45 degrees and where the center is at 90 degrees.

Straight lines can't curve. It's the individual lines that are positioned at different angles that make it seem like it curves.