Types of Triangles and Quadrilaterals

“I can draw and label 2-D figures.”

Triangles

Follow the presentation with your note sheet to write down facts about certain triangles.

Equilateral Triangles

Equilateral triangles have: 3 sides of the same

length 3 angles of the

same measure.

Equilateral triangles are regular polygons.

Isosceles Triangles

Isosceles triangles have: 2 sides of the same

length 2 angles of the

same measure

Scalene Triangles

Scalene triangles have: No sides of equal

length No angles of equal

measure

Right Triangles

Right triangles have: 1 right (90°) angle.

A right triangle is exactly ½ of a rectangle’s area.

Right-Isosceles & Right-Scalene Triangles

Right-Isosceles triangles have: 1 right (90°) angle 2 sides of the same

length Right-Scalene

triangles have: 1 right (90°) angle no sides of the

same length

Acute Triangles

Acute triangles have: 3 acute angles (all

angles less than 90°)

Obtuse Triangles

Obtuse triangles have: One obtuse (greater

than 90°) angle.

Quadrilaterals

Turn over the page and follow the presentation with your note sheet to write down facts about certain quadrilaterals.

Rectangles

Rectangles: Every angle is a

right angle (90°) Opposite sides are

parallel and the same length

Squares

Squares: Have 4 sides and

every angle is a right angle (90°)

Opposite sides are parallel

All sides are the same length

Parallelograms

Parallelograms: Opposite sides are

parallel and equal in length

Opposite angles are equal

Rhombus

Rhombus: Has 4 sides of

equal length Opposite sides are

parallel Opposite angles are

the same

Trapezoid

A trapezoid has 1 pair of opposite sides that are parallel.

Isosceles Trapezoid

The sides that are not parallel are the same length

The angles coming from a parallel side are equal.

Now see if you can use your notes to identify or create different 2-D shapes