Sketching a quadratic graph Sketch the graph of the following quadratic function f(x) or y = -5+x-x 2 Show clearly the coordinates of the points where the curve crosses both the coordinate axes, the line of symmetry and the coordinates of the vertex. Mr Petros Tsichlakis

Model Answer 1)SHAPE Since a = -1 is negative, our parabola is a ∩ shape. 2) y-crossing Since c = -5, our curve crosses the y axis at y=-5 Alternatively: We set x=0 in the equation y = -5+x-x 2 and this will give us the value of y: f(0) = y = -5+0 – 0 2 = -5 Coordinates of y-crossing (0,-5) Our equation is a quadratic of the form y=ax 2 +bx+c therefore a=-1 b=1 and c=-5 Mr Petros Tsichlakis

y x Mr Petros Tsichlakis