1. Maths Unit 23 – Pythagoras & Trigonometry
Pythagoras is used to find a missing side when 2 other sides are known
Example
Trigonometry is used to find a missing angle when 2 sides are given or a missing side when one angle and side are given.
1. Is it a right angled triangle?
2. Label the triangle
3. Decide which triangle to use
Opposite
4. Use the cover up method to decide what calculation to do
Hypotenuse
10m
_____ = 5.8m (1dp)
Tan (60)
Adjacent
Key word definitions
Pythagoras Theorem - In a right angled triangle the square of the long side is equal to the sum of the squares of the other two squares. It is stated in the formula a2 + b2 = c2.
Right Angled Triangle – A triangle with a 90° angle in it.
Squaring – The result of multiplying a number by itself.
Square Rooting – The square root of a number is a value that when multiplied by itself, gives the number. E.g. 4 x 4 = 16 so the square root of 16 is 4.
Trigonometry – part of mathematics which deals with relationships between angles and sides of triangles.
Hypotenuse – the longest side of a right angled triangle. The side opposite the right angle.
Adjacent- the side of the triangle that is next to the angle given or in question (excluding the right angle)
Opposite – the side opposite the angle given or the angle in question (excluding the right angle)