Algebra II Elements 5.2: Graph quadratic function in vertex or intercept form HW: p.232 (36-48 even) Tomorrow: projects are due, midterm review.

Vertex Form  y = a(x – h) 2 + k Vertex: (h, k) Vertex: (h, k) Line of symmetry: x = h. Line of symmetry: x = h.  Steps in graphing: 1.) Plot vertex (h, k). 2.) chart and plot points.

Graph y = 2(x – 4) 2 – 1 X Y

Graph y = (x + 1) X Y

Graph y = -2(x + 1) X Y

Intercept form  Steps in graphing intercept form y = a(x – p)(x – q) Plot the x-intercepts: points p and q Plot the x-intercepts: points p and q x-coord of vertex = average p & q. x-coord of vertex = average p & q. Find y-coordinate of vertex by plugging in. Plot the vertex. Find y-coordinate of vertex by plugging in. Plot the vertex.

Graph y = (x + 2)(x – 2)

Graph y = 3(x + 3)(x + 5)

Graph y = -2(x + 1)(x – 2)

3 types of graphs 1.) Standard Form: y = ax 2 + bx + c 1.) x-coordinate of vertex: 2.) chart with vertex in the middle 2.) Vertex Form: y = a(x – h) 2 + k 1.) vertex: (h, k) 2.) chart with vertex in the middle 3.) Intercept Form: y = a(x – p)(x – q) 1.) x-intercepts: p and q 2.) x-coordinate of vertex: average p and q. Find y by plugging in.

Graph 1.) y = (x – 4)(x – 2) 2.) y = 3x 2

Graph 3.) y = -2x ) y = (x – 2) 2

Graph 5.) y = 1/2(x + 1)(x – 2) 6.) f(x) = -x 2 - 2x - 1

Graph 7.) y = 3x 2 + 6x – 4 8.) y = ½x 2