This Self-Learning Module (SLM) is prepared so that you, our dear learners, can continue your studies and learn while at home. Activities, questions, directions, exercises, and discussions are carefully stated for you to understand each lesson.

Each SLM is composed of different parts. Each part shall guide you step-by-step as you discover and understand the lesson prepared for you.

Pre-tests are provided to measure your prior knowledge on lessons in each SLM. This will tell you if you need to proceed on completing this module or if you need to ask your facilitator or your teacherâ€™s assistance for better understanding of the lesson. At the end of each module, you need to answer the post-test to self-check your learning. Answer keys are provided for each activity and test. We trust that you will be honest in using these.

Please use this module with care. Do not put unnecessary marks on any part of this SLM. Use a separate sheet of paper in answering the exercises and tests. And read the instructions carefully before performing each task.

This module was designed in order to assist you to learn the different kinds of triangles and quadrilaterals.

In this lesson, you will learn about the different kinds of triangles according to sides and angles and identify and describe the different kinds of quadrilaterals: square, rectangle, parallelogram, trapezoid, and rhombus. You will also describe the different attributes/properties of triangles using concrete objects/models. The learning activities will allow you to explore, discover and appreciate the different kinds of triangles that can be seen in different objects around us. You will also be taught on how to describe and illustrate the different kinds of triangles in the succeeding activities.

After going through this module, you are expected to:

1. describe the attributes/properties of triangles and quadrilaterals using concrete objects or models;

2. identify and describe triangles according to sides and to angles; and

3. identify and describe the different kinds of special quadrilaterals: square, rectangle, parallelogram, trapezoid, and rhombus.