❖ In this lesson, we explain the Exterior Angle Theorem of a triangle using clear visuals and step-by-step examples.

You’ll learn what an exterior angle is, how it relates to linear pair angles, and why it’s always equal to the sum of the two remote interior angles.

We’ll also show why this theorem works by comparing the triangle’s angle sum with a straight angle formed by a linear pair, then apply it to solve four clear examples.

🎯 Key concepts covered:

✔ What is an exterior angle?

✔ How many exterior angles can a triangle have?

✔ Why we consider only three exterior angles in the triangle

✔ What are linear pair angles?

✔ A simple proof of the theorem

✔ Four step-by-step examples

✅ This lesson will help you fully understand the Exterior Angle Theorem and apply it confidently in geometry problems.