Classifying shapes

8 videos
3 skills
In this tutorial, we'll classify two-dimensional figures based on the presence or absence of parallel or perpendicular lines, or the presence or absence of angles of a specified size. We'll also learn about special triangles called "right triangles". Common Core Standard: 4.G.A.2

Quadrilateral overview

VIDEO 8:24 minutes
"Quad" means "four" and "lateral" means "line." A quadrilateral is literally a shape with four sides (lines) and four angles. Let's learn the difference between concave and convex quadrilaterals as well as trapezoids, parallelograms, and ...

Quadrilateral properties

VIDEO 5:07 minutes
How about this: we are given a 4-sided shape and asked to determine whether its properties qualify it to be called a quadrilateral (or category of quadrilaterals). Check it out.

Quadrilaterals: kites as a geometric shape

VIDEO 5:38 minutes
Is a kite a quadrilateral? Is it a rhombus? A parallelogram? Let's find out.

Quadrilaterals: find the type exercise

VIDEO 2:49 minutes
Take a look at the given data and determine what type of quadrilateral we have.

Quadrilateral types

PRACTICE PROBLEMS
Identify quadrilaterals based on pictures or attributes.  Quadrilaterals included are parallelograms, rhombuses, rectangles, and squares.

Triangles: categorization by angle or equal sides.

VIDEO 6:00 minutes
Scalene, isosceles, equilateral, acute, right, obtuse. All are types of triangles but what makes them special depends on the method of categorization. Watch this outstanding explanation.

Triangles: using angles to categorize

VIDEO 5:30 minutes
You say you can't categorize a triangle because you don't know the length of the sides. Guess what? If you know the size of the angles you can!

Categorizing triangles

VIDEO 2:23 minutes
Let's practice categorizing triangles in this example exercise.

Recognizing triangle types

PRACTICE PROBLEMS
Identify triangles by their angles as acute, right, or obtuse.  Identify triangles by their side-lengths as equilateral, isosceles, or scalene.

Categorizing geometric shapes: practice examples

VIDEO 2:15 minutes
Watch and do these example exercises along with us. Remember what you have learned about perpendicular lines, right, obtuse, and acute triangles.

Classifying shapes by line and angle types

PRACTICE PROBLEMS
Classify shapes based on pictures or attributes, such as angle types and side-lengths.