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9.5 Solving Quadratic Equations by Graphing Ms. Wu • Place a sticky note on any three posters… • RED – need most help – need some help • GREEN – good to go! Warm-Up • • • • Warm-Up (5 min.) Reminder 101 (3 min.) Review (10 min.) Quiz, Evaluation, Folder Organization ( 27 min.) • Introduction (5 min.) • 9.5 Workshop (20 min.) • In-Class Assignment (20 min.) Objectives Remind 101 – 3rd th Remind 101 – 4 Axis of Symmetry x = 2 Domain: all real numbers y-int (0, 3) Range: y ≥ -1 Opens UP Zeros: 1 and 3 Review Vertex (2, -1) Minimum For the parent function, y = x2, what is the transformed function that is ____________? • 7 units up: y = x2 + 7 • 2 times wider: y = ½x2 • 1/3 times narrower and down 1 unit: y = 3x2 – 1 Review For the function, y = x2+2x-1, what is the ________? • • • • • • • Axis of symmetry? x = Vertex: (-1, -2) Does it open up or down? UP Is it a maximum or minimum? MINIMUM y-intercept: (0, -1) Domain: all real numbers Range: y ≥ -1 Review Quiz -> Evaluation - > Organization -> Lunch Is your folder ready for an organization grade?? • Notes • 9.1 • 9.2 • 9.3 • 9.4 • Roller Coaster • 1st Blueprint • 2nd Blueprint • Homework • 9.1 • 9.2 • 9.3 • 9.4 Everything must be completed…folders will be picked up for a grade next class period!! • In-Class Assignments • 9.2 Exploration (Axis of Symmetry) • 9.4 Transformers Exploration • Go to Ms. Wu’s website: annwustudentteaching.webs.com • Go to the tab “For Students (3rd & 7th)” • New Format: • Homework: Watch videos, take notes • In-Class: Work on assignment, get help, quiz Announcement • A quadratic function is a function that can be written in the standard form y = ax2+bx+c. • A quadratic equation is an equation that can be written in the standard form 0 = ax2+bx+c. • When writing a quadratic function as its related quadratic equation you replace y with 0. Then, you solve the equation by finding its zero(s) or roots or x-int. Solving Quadratic Equations by Graphing Ms. Wu’s hint: Remember to move everything to one side until you have everything equal to 0! • Examples: • 1. x2-8x-16=2x2 -x2-8x-16 = 0 zero: -4 • 2. 6x+10=-x2 x2+6x+10=0 • 3. –x2+4 = 0 zeros: -2, 2 zero: none • Video: Parabolic Solar Ovens in Coast Rica • Video: How to Cook Food Using Solar Ovens Parabolic Solar Ovens Joseph is trying to build a solar oven in his backyard to cut down on the cost of electricity. He did some research and found that the sun’s rays are best captured by the quadratic function y = x2 -8x+12. Question: Joseph needs to buy a parabolic mirror at Lowe’s, how wide should the diameter of the mirror be? Mirror needs to be 4 feet in diameter. • Complete the evens on 9-5. Turn in by the end of class. • Homework: complete notes on how to FOIL and FACTOR. Watch videos online. Organize folder!! In-Class & Homework