This model can be used to predict the fuel consumption of a car, y y\,y miles per gallon, for a car travelling at x x\,x miles per hour.
y=60−0.025(x−55)2 y = 60 - 0.025(x - 55)^2 y=60−0.025(x−55)2Deduce the speed at which the car has the greatest fuel efficiency.
211 exam-style questions on Edexcel A Level Maths Quadratics, covering 2.1 Solving Quadratics, 2.2 Completing the Square, 2.3 Sketching Quadratic Graphs, 2.4 The Discriminant, and 2.5 Modelling with Quadratics. Each one has a worked solution and a mark scheme showing where the marks go.