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6.6 Analyzing Graphs of Quadratic Functions. Write a Quadratic Equation in Vertex form. Vertex form of the Quadratic Equation. So far the only way we seen the Quadratic Equation is ax 2 + bx + c =0. This form works great for the Quadratic Equation. Vertex form works best for Graphing.
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6.6 Analyzing Graphs of Quadratic Functions Write a Quadratic Equation in Vertex form
Vertex form of the Quadratic Equation So far the only way we seen the Quadratic Equation is ax2 + bx + c =0. This form works great for the Quadratic Equation. Vertex form works best for Graphing. We need to remember how to find the vertex. The x part of the vertex come from part of the quadratic equation.
Vertex form of the Quadratic Equation The x part of the vertex come from part of the quadratic equation. To find the y part, we put the x part of the vertex. The vertex as not (x, y), but (h, k)
Write the Quadratic Equation in Vertex form Find a, h and k a= 1 h = -1 k = 3
Write the Quadratic Equation in Vertex form Find a, h and k a= 1 h = -1 k = 3
Vertex is better to use in graphing y = 2(x - 3)2 – 2 Vertex (3 , -2) Put in 4 for x, y = 2(3 - 4)2 – 2 (4, 0) Then (2, 0) is also a point
Let see what changes happen when you change “a” The larger the “a”, the skinner the graph What if “a” is a fraction?
Let see what changes happen when you change “a” What if “a” is a fraction?
What if we change “h” in the Vertex Let a = 1, k = 0 Changing the “h” moves the graph Left or Right.
What if we change “k” in the Vertex Let a = 1, h = 0 “k” moves the graph up or down.
Write an equation Given the vertex and a point on the graph. The vertex gives you “h” and “k”. We have to solve for “a” Given vertex (1, 2) and point on the graph passing through (3, 4) h =1; k = 2
Write an equation Given vertex (1, 2) and point on the graph passing through (3, 4) x=3, y=4 Solve for “a”
Write an equation a = ½ Solve for “a”
Write an equation a = ½ Final Answer
Homework Page 326 – 327 # 15 – 25 odd, 27, 31, 39 – 45 odd
Homework Page 326 – 327 # 16 – 26 even, 28, 32, 40 – 46 even