A curve has equation y=x2+(k−1)x+9y = x^2 + (k - 1)x + 9y=x2+(k−1)x+9 where k k\,k is a constant.
The line with equation y=3xy = 3xy=3x is a tangent to the curve.
Find the possible values of kkk.
63 exam-style questions on AQA A Level Maths 1.5.3 Quadratic functions. Each one has a worked solution and a mark scheme showing where the marks go.