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Warm-up. Solve the following quadratics. 2x 2 – 3x – 9 = 0 2) 2(x–5) 2 – 6 = 0 3) x 2 + 6x – 11 = 0. Homework Review. EOCT Review. Question of the Day. CCGPS Geometry Day 53 (10-25-13). UNIT QUESTION: How are real life scenarios represented by quadratic functions?
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Warm-up Solve the following quadratics. • 2x2– 3x – 9 = 0 • 2) 2(x–5)2– 6 = 0 • 3) x2 + 6x – 11 = 0
EOCT Review Question of the Day
CCGPS GeometryDay 53 (10-25-13) UNIT QUESTION: How are real life scenarios represented by quadratic functions? Today’s Question: When is it useful to solve quadratics by the quadratic formula? Standard: MCC9-12..A.REI.4b
The discriminant is a small part of the quadratic formula. notes There is a way to tell how many roots an equation will have. It’s called finding the discriminant.
If the answer is POSITIVE, then you will have 2 roots. If the answer is ZERO, then you will have 1 root. If the answer is NEGATIVE, then you will have no roots. Our text book says solutions instead of roots (same thing).
Find the number of x-intercepts.Example: 4 two x-intercepts
Find the number of x-intercepts.Example: 5 zero x-intercepts
Quadratic Formula: gives the solution of in terms of the coefficients a, b & c. The solutions of the quadratic equation are
1st 2nd Ex: 1 Solve x2+ 9x +14 = 0 a = b = c =
example #2 1 and 3
Try these on your own: -5/2 & 2 -1 & 4 2.89 & -1.39
Rocket A rocket is shot upward with an initial velocity of 125 feet per second from a platform 3 feet above the ground. Use the model to find how long it will take the rocket to hit the ground. t = 7.83 seconds 3 ft
Class work • Quadratic Formula Worksheet
HOMEWORK • Solving Quadratics by All Methods WS