Count the Vertices: Identifying Points A through J in a Geometric Figure

Question

How many vertices are shown in the figure?

00:00 How many perpendicular lines are in the drawing?

00:03 A perpendicular line is a line that creates a right angle at its intersection point with another line

00:07 Therefore all these lines are perpendicular

00:21 And this is the solution to the question

Note that perpendicular lines are straight lines that create a 90-degree angle at their intersection point.

Let's locate the intersection points that create right angles in the drawing:

The lines that create the marked right angles are:

AB is perpendicular to CD

AB is perpendicular to EF

EF is perpendicular to IJ

IJ is perpendicular to GH

Therefore, there are 4 perpendicular lines in the drawing.