Explain to her how she can get a good sketch of the graph of the function
without using a calculator and without having to make an x → y table. Be sure to explain how to locate the vertex, whether the parabola should open up or down, and how its shape is related to the shape of the graph of .
Where will the vertex be? Does the parabola open up or down? Is it vertically stretched?
Your friend also needs to know the x- and y-intercepts. Show her how to find them without having to draw an accurate graph or use a graphing calculator.
Substitute 0 for x and solve for y to find the y-intercepts.
Substitute 0 for y and solve for x to find the x-intercepts.