A quadrilateral is a closed, two-dimensional shape composed of exactly four straight sides, four vertices, and four angles. Identification depends on these defining attributes rather than orientation, size, or appearance, so squares, rectangles, and other four-sided shapes can be recognized in varied arrangements, while shapes with curved or more than four sides are excluded; this classification supports later work with shape attributes, perimeter, and area.
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Detailed Explanation: Identify quadrilaterals
A quadrilateral is a closed shape with exactly 4 straight sides. It also has 4 vertices (corners) and 4 angles.
The shape can be turned, stretched, or tilted. Its position and size do not matter. What matters is counting its sides and checking that they are straight and connected.
Example: Is this shape a quadrilateral?
B
/ \
A C
\ /
D
Step 1: Check that the shape is closed.
The sides connect all the way around from to to to and back to .
Step 2: Count the straight sides:
There are exactly straight sides.
Step 3: Count the vertices, or corners.
The vertices are , , , and , so there are vertices.
Because the shape is closed and has exactly straight sides, it is a quadrilateral.
Learn by doing: Identify quadrilaterals
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Practice:
Classifying Polygons by Sides
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Download/Modify Free Grade 2 'Identify quadrilaterals' Worksheet
Print this free 'Identify quadrilaterals' worksheet to practice this skill away from the computer. Click 'Modify' to easily customize this worksheet to your exact needs.
This Worksheet Includes:
- Classifying Polygons by Sides
- Quadrilaterals
- Shapes - 2D Complex
- Quadrilaterals (Real World)
- Polygons - Number of Sides to Name
- Polygons - Number of Sides to Name - First Time
- 2D Shapes by Vertex Count
- Shapes - 2D Simple (Real World)
Units Teaching This Skill
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