Geometry Scrapbook

By:Hayden Mouser



A point specifies only location; it has no length, width, or depth.



A line has only one dimension: length. It continues forever in two directions (so it has infinite length), but it has no width at all. A line connects two points via the shortest path, and then continues on in both directions.


A plane is a flat, two-dimensional object. We often represent a plane by a piece of paper, a blackboard, or the top of a desk. In fact, none of these is actually a plane, because a plane must continue infinitely in all directions and have no thickness at all. A plane can be defined by two intersecting lines or by three non-collinear points.

Intersecting Lines

Two or more lines that meet at a point are called intersecting lines.

Parallel lines

Parallel lines are two lines in the same plane that never intersect. No matter where you measure, the perpendicular distance between two parallel lines is constant.


A pentagon is a polygon with five sides.


A 6-sided polygon (a flat shape with straight sides).


An octagon is a geometrical shape that contains eight sides and eight angles.


A polygon having ten angles and ten sides.


A three-dimensional shape that looks like a ball.

Acute Angle

An angle that is less than 90°.

Obtuse Angle

An angle that is greater than 90° but less than 180°.

Right Angle

An angle that is 90° exactly.


A square is a regular quadrilateral, which means that it has four equal sides and four equal angles.


A square is a regular quadrilateral, which means that it has four equal sides and four equal angles.


A trapezoid is a quadrilateral that has one pair of opposite sides that are parallel.


A rhombus is a quadrilateral that has all four sides congruent.


A pyramid is a polyhedron formed by connecting a polygonal base and a point, called the apex.


A solid with six congruent square faces.


The plane figure formed by connecting three points not in a straight line by straight line segments; a three-sided polygon.


A circle is a shape with all points the same distance from its center.

Horizontal Line

A horizontal line is one which runs left-to-right across the page.

Vertical Line

A vertical line is one which runs up and down the page.

Parallel Planes

Planes that never intersect each other.


A cone is a three-dimensional geometric shape that tapers smoothly from a flat base (frequently, though not necessarily, circular) to a point called the apex or vertex.

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