is for acute

An acute triangle is a triangle with all three angles acute (less than 90°).

A triangle measures 180 degrees.



An equiangular acute triangle has all angles measuring 60 degrees.

is for base

A base can be:

1. the bottom line of a two dimensional shape or

2. the bottom face of a three dimensional face.

The base is what objects "sit" on; it is the flat bottom part.

A cone is composed of a circular or elliptical base, and a curved surface which tapers to a point.

An example is an ice cream cone.

The point at the end of a cone is called a vertex.

is for diamond

A plane shape with 4 equal sides.

This shape has NO right angles.

Also known as a Rhombus.

is for ellipse

An oval-shaped plane, resembling a flattened circle.

Fun fact: all planets move in elliptical-shaped orbits

Ellipses have minor and major axes: the longer diameter is the major, and the shorter the minor.

is for face

The flat surface of a three dimensional shape.

example: a cube has 6 faces

The sides of a face are called edges, and the corners are called vertices.

is for Geometry

The study of size and shape of points, lines, angles, surfaces, and solid figures.

A triangle is an example of a 2D geometrical shape.

The origin of the word 'Geometry': It comes from a Greek word- ‘Geo’ meaning ‘Earth’ and ‘Metria’ meaning ‘Measure’. So basically it is the measurement of Earth. 

is for hexagon

 A hexagon is polygon with six sides.

Fun fact: Bees make honeycomb in hexagonal shapes

The total measurement of the interior angles is 720 degrees.

is for isosceles triangle

This triangle that has two sides equal in length. 

Its base angles are equal.

Memory trick for isosceles: "eye"sosceles has two matching sides and angles, like we have two eyes.

is for jagged

A shape that is jagged has concave and convex angles.

Concave polygons have an interior angle greater than 180 degrees.

A way to remember 'concave' is that it "caves in"

A kite is a plane shape with two sets of equal lines, and one set of equal angles.

Fun Fact: the

longest kite in

the world is 3,394 feet high

A kite is a quadrilateral

is for line of symmetry

An object or shape has a line of symmetry if it can be divided into two equal and identical parts by that line.

An example is a butterfly or flower

Objects can have more than one line of symmetry

is for mass

The quantity of matter in an object.

This can of soup is 305 grams, a measurement of mass.

Mass equals density times volume

is for n-gon

a polygon with n sides

some examples include the shapes on the left.

The prefix states the number of sides of the polygon

is for obtuse

An obtuse angle is an angle greater than 90 degrees and less than 180 degrees.

An obtuse triangle has one obtuse angle.

There are five classifications of angles based on its degrees measurement

is for pyramid

A three dimensional shape with a polygon as its base and all other faces congruent triangles that meet at the top (its vertex).

The base can be a triangle, square, or other polygon

Fun Fact: the first pyramid shape was used in ancient Mesopotamia, not Egypt.