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7.5 Graphing Parabolas (Standard Form). Today’s Date: 1/13/12. Notes on Handout. Ch 7.5 – 7.7 BIG QUIZ is on Fri 1/20. Graphs of Parabolas. “Normal” Vertex (0, 0) Right 1 Up 1 Left 1 Up 1 Right 2 Up 4 Left 2 Up 4. “Skinny”. “Wide”. Properties of Parabolas. Standard Form:.
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7.5 Graphing Parabolas (Standard Form) Today’s Date: 1/13/12 Notes on Handout Ch 7.5 – 7.7 BIG QUIZ is on Fri 1/20
Graphs of Parabolas “Normal” Vertex (0, 0) Right 1 Up 1 Left 1 Up 1 Right 2 Up 4 Left 2 Up 4 “Skinny” “Wide”
Properties of Parabolas Standard Form: 1) Which way does it open? Wide or skinny? “a” is positive – opens UP “a” is negative – opens DOWN │a│> 1 skinny │a│< 1 wide │a│= 1 normal fraction
Properties cont… 2) Axis of Symmetry (A of S) 3) Vertex:
Properties cont… 4) Is the vertex a MAXIMUM or MINIMUM point? a = (–) If opens down, vertex is MAX If opens up, vertex is MIN a = (+) 5) Extreme value: “y” part of the vertex
Properties cont… ( , 0) when y value is zero 6) x-intercepts: 7) y-intercepts: ( 0, c) c is y-intercept from SF • Table of values: • (only if you need to) x y 9) Graph
Ex 1) Graph 1) Which way does it open? Wide or skinny? “a” = 3 is positive – opens UP │3│> 1 → skinny Equation!! 2) Axis of Symmetry (A of S)
Ex 1 cont… 3) Vertex: 4) Is the vertex a MAXIMUM or MINIMUM point? a = (+) Opens up, vertex is MIN 5) Extreme value:
Ex 1 cont… ( , 0) 6) x-intercepts: 7) y-intercepts: ( 0, 1)
Ex 1 cont… • Graph • Use the A of S • Normal: Up 1 right 1 • a = 3: Up 3 right 1 • Up 3 left 1 • Table of Values: • Didn’t need it, but if you do, choose easy points for x and solve for y • Usually: Choose -2, -1, 0, 1, 2 for x
Homework #708 Practice Properties WS