# Coordinate Geometry

Objectives:

You should know how to
• Plot coordinates on the Cartesian Plane
• Use the formula to calculate Gradient of a straight line
• Find the equation of a straight line
• Know the different ways of writing a straight line equation
• Sketch equations of y = mx + c, y = k, x = k where m, c and k are constants
• Use the graphical method to solve simultaneous equations
• Find distance and mid-point of 2 points using formula [Learn Pythagoras Theorem first]

Resources: Notes and Textbook Ch 5

### (1) Background reading

Read up about the Mathematician who developed the Cartesian Coordinate System - Rene Decartes

### (2) Concept Mastery

Notes to use along with the slides:

## (a) The Cartesian Coordinate System and Gradient of a straight line

These are the slides for this section:

Test your knowledge on plotting of coordinate points by playing these 2 games:

(1) http://www.onlinemathlearning.com/grid-game.html

## (b) Equation of a straight line

Concepts and Formulas:
(1) Gradient/Slope of a line:

(2) Equation of a straight line

The powerpoint slides show a summary of the formulas. You can use the slides as a reference for your practice.

Game on Equation of straight line: http://www.bbc.co.uk/education/mathsfile/shockwave/games/planethop.html

(3) How to intepret Equations of straight lines:

(4) Parallel Lines (Perpendicular Lines are also mentioned in the video but it's not required at Sec 2 Level)

(5) Further Examples on equations of parallel and perpendicular lines: