Summary
In trigonometry, bearings are used to describe the direction of one point from another using angles measured clockwise from the north. Scale drawings represent real-world distances on paper using a specific scale, such as 1 cm to 15 km. Pythagoras' Theorem is used to calculate the length of a side in a right-angled triangle. Example: If a ship sails from port A to port B on a bearing of 146°, the bearing is the angle measured clockwise from north. Example: A scale drawing shows port A and port B with a scale of 1 cm to 15 km. Example: To find the distance ST when port T is 267 km east and 356 km north of port S, use Pythagoras' Theorem.
Exam Tips
Key Definitions to Remember
- Bearings are angles measured clockwise from the north.
- Scale drawings use a specific scale to represent real-world distances on paper.
- Pythagoras' Theorem relates the lengths of sides in a right-angled triangle.
Common Confusions
- Confusing the direction of bearings with counterclockwise measurements.
- Misinterpreting the scale on a drawing.
Typical Exam Questions
- What is the bearing of port B from port A? Measure the angle clockwise from north.
- How do you calculate the distance using a scale drawing? Use the scale to convert measurements on the drawing to real-world distances.
- How do you find the length of a side using Pythagoras' Theorem? Use the formula a² + b² = c² for right-angled triangles.
What Examiners Usually Test
- Ability to measure and interpret bearings correctly.
- Understanding and application of scale drawings.
- Correct use of Pythagoras' Theorem to solve problems.