Basic Shapes & Angles

$Basic Geometry$

Basic Shapes & Angles: At a Glance

Introduction to Basic Shapes & Angles:

This is where it all begins: basic shapes, lines, and angles.

Read on and let us take you on a magical geometry tour...

Name	Description	Example
Point	A single location. Usually drawn as a dot. It is "dimensionless". Labeled as Point P. You used these when playing Connect the Dots.
Line	A straight path passing through at least two points. Extends in both directions forever. Labeled as Think of this as a highway that never ends.
Line Segment	A portion of a line. It has limits at each end. Labeled as You've drawn these since you were 1½!
Ray	A straight path with one terminal point and extending indefinitely in the other direction. Labeled as Make sure to start with the terminal point and extend past the other point. Rays are an easy image. Picture the sun as a terminal point and its rays extending indefinitely into space.
Plane	A flat surface without boundaries. Labeled by naming three nonlinear points on the plane, Plane GHI. Planes are somewhat difficult to imagine. It's like a piece of paper that extends in every direction forever.
Parallel Lines	Lines that lie on the same plane and never intersect. Labeled as Look at a piece of lined paper. All the horizontal lines are parallel to each other.
Perpendicular Lines	Lines that intersect at a 90° angle. Labeled as On that same lined paper the vertical margin lines are perpendicular to the horizontal ones.

Refer to the following diagram for the examples below

Plane

Plane Example

Two parallel lines
Two sets of perpendicular lines
Many ways to name the plane	Plane EBF. This plane can be named numerous ways as long as you use three points that are not in a line.
There are many rays in this picture, here are three for example

Exercise 1

What is the intersection of two unique, non-parallel lines?

Hint

imagine two straws meeting

Exercise 2

What is the intersection of two unique, non-parallel planes?

Hint

imagine two pieces of paper meeting

Exercise 3

How many dimensions does a plane have?

Hint

there is width and length