Describe typical examples of direct variation/proportion
Apply the language of direct variation to everyday contexts: y is directly proportional to x, y is proportional to x, y varies directly as x
Identify and represent direct variation/proportion as y∝x (y is proportional to x) or y=kx, where k is the constant of variation
Describe typical examples of inverse (indirect) variation
Apply the language of inverse variation to everyday contexts: y is inversely proportional to x, y is inversely proportional to x, y varies inversely as x
Identify and represent inverse variation/proportion as y∝x1 (y is inversely proportional to x) or y=xk, where k is the constant of variation
Recognise and describe direct variation from graphs, noting that the graph of y=kx is a straight line passing through the origin, with its gradient k being the constant of variation
Recognise and describe inverse variation from graphs, noting that the graph of y=xk is a curve