In 1960 the life expectancy in the UK was 70 years In 1975 the life expectancy in the UK was 74 years Given that x x\,x years is the life expectancy n n\,n years after 1960.
Using a linear model, form an equation linking x x\,x with nnn.
260 exam-style questions on Edexcel A Level Maths Straight Line Graphs, covering 5.1 y = mx + c, 5.2 Equations of Straight Lines, 5.3 Parallel and Perpendicular Lines, 5.4 Length and Area, and 5.5 Modelling with Straight Lines. Each one has a worked solution and a mark scheme showing where the marks go.