# 4.2: Graphs of Quadratic Functions in Vertex or Intercept Form

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4.2: Graphs of Quadratic Functions in Vertex or Intercept Form
Objectives: To graph quadratic functions in vertex and intercept form To rewrite a quadratic equation in standard, vertex, or intercept form

To graph y = a(x – h)2 + k : Use the a-value to determine  or  Plot the vertex (h, k) Graph the axis of symmetry x = h Find and plot at least two other function values and their reflections x- and y-intercepts? Draw a parabola through the points

Exercise 1 Graph First find the axis of symmetry
Remember y = a(x – h)2 + k Axis of symmetry x= h And x = -2 GRAPH X= -2

Exercise 1 Graph Now find the vertex. (h,k) (-2,3) Plot the point.

Exercise 1 Graph Now find the vertex. (h,k)
Pick two values for x and find its matching coordinate point for y. x=-1 y = -(-1+2)^2 + 3 = -(1)^2 + 3 = = 2 Plot (-1, 2)

Exercise 1 Graph Now find again when x = 0 x=0 y = -(0+2)^2 + 3
= -(2)^2 + 3 = = -1 Plot (0, -1)

Exercise 1 Graph REFLECT(MIRROR) THE POINTS!!