Lesson Notes By Weeks and Term v4 - SHS 1

Lesson Video

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Performance objectives

• Explain the Pythagorean theorem.
• Solve problems using the formula a² + b² = c².
• Verify if a triangle is a right triangle.
• Apply the theorem to real-life situations.

Lesson summary

The Pythagorean Theorem is a fundamental principle in geometry that has been used for thousands of years, from the ancient Egyptians building pyramids to a modern carpenter in Kumasi ensuring a door frame is perfectly square. It provides a powerful and simple relationship between the sides of a right-angled triangle. Understanding this theorem helps us solve many practical problems in construction, farming, navigation, and even art. It is a cornerstone of our ability to measure and understand the space around us.

Lesson notes

A. What is a Right-Angled Triangle?

A right-angled triangle is any triangle that has one angle measuring exactly 90 degrees. This 90° angle is often marked with a small square symbol (└).

The sides of a right-angled triangle have special names: Legs (or Cathetus): The two sides that meet to form the right angle. We often label them a and b. Hypotenuse: The side opposite the right angle. It is *always* the longest side of the triangle. We label it c. B. The Pythagorean Theorem

The theorem, named after the Greek mathematician Pythagoras, states:

Evaluation guide

• Solve problems on Pythagorean theorem by identifying situations that involve right
• triangles, verify the formula and apply it.
• Collaborative learning: In small groups, engage learners to research and discuss to come out with
• an explanation, using illustrations, why the Pythagorean theorem only applies to right triangles.