Exploring the properties of linear functions SC

Students should be able to identify the gradient and intercept of linear functions. They should be able to find the equation of the line through two given points, or through one point with a given gradient and interpret the gradient of a straight line graph as a rate of change.

When plotting linear graphs some pupils may draw a line segment that stops at the two most extreme points plotted

Some possible misconceptions include not rearranging the equation of a straight line given in an alternative form. For example, they may suggest that the line y – 4x = 12 has a gradient of -4. Some students may think that gradient = (change in x) / (change in y)’ If they understanding of gradient is not secure students may think that the horizontal section of a distance time graph means an object is travelling at constant speed or that a section of a distance time graph with negative gradient means an object is travelling backwards or downhill.