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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
"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 ...
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.
Is a kite a quadrilateral? Is it a rhombus? A parallelogram? Let's find out.
Take a look at the given data and determine what type of quadrilateral we have.
Identify quadrilaterals based on pictures or attributes. Quadrilaterals included are parallelograms, rhombuses, rectangles, and squares.
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.
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!
Let's practice categorizing triangles in this example exercise.
Identify triangles by their angles as acute, right, or obtuse. Identify triangles by their side-lengths as equilateral, isosceles, or scalene.
Watch and do these example exercises along with us. Remember what you have learned about perpendicular lines, right, obtuse, and acute triangles.
Classify shapes based on pictures or attributes, such as angle types and side-lengths.