Solve by Completing the Square 1. x 2 - 4x + 7 = 0 2. x 2 + 8x = 2 3. x 2 - 2x = -9 (Save room, we have a reloop warm up next!)
1. If 3x is one factor of 3x 2 – 9x, what is the other factor? 2. When x 2 – 9 and x 2 – 5x + 6 are factored, a common factor is what? 3. Factor completely 72a 3 b 4
A radical expression contains a square root. A radicand, the expression under the radical sign, is in simplest form if it contains no perfect square factors other than 1. Using prime factorization we can simplify radical expressions. Radical or Square Root Radicand
X 2 = ______ 16 = _______ 49 = _______
Examples: 1. 2.
Examples: 1. 2.
3. 4.
On the half sheet… ◦ Simplify each radical, WITHOUT a calculator! The first group done with ALL correct answers gets CANDY!
Graphing –not always exact. need a graphing calculator to find exact values. don’t always have a solution. Factoring – doesn’t always work. only use when factors are easy to find. Quadratic Formula – always works and get exact values. need a 4-function calculator with a square root button to approximate.
Pop Goes the Weasel Pop Goes the Weasel Gilligan Gilligan Mrs. Sawyer’s Way
Standard Form of a Quadratic: ax 2 + bx + c = 0, where a ≠ 0. Song 1: Frere Jacque --opposite b, opposite b --plus or minus square root --b squared minus 4ac --all over 2a, all over 2a Song 2: Pop Goes the Weasel x equals negative b plus or minus the square root of b squared minus 4ac all over 2a
Create a song or poem to help remember the Quadratic Formula. ◦ +5 points on test Perform it for the class. ◦ +10 points ◦ extra points will be awarded for level of creativity during the performance Due by Wednesday, March 6 th
1. Use 2 methods to solve x 2 – 2x – 24 = 0 Factoring:Quadratic Formula:
2. Use 2 methods to solve x = 18x Factoring:Quadratic Formula:
3. Solve 4x 2 – 2x = 7 Quadratic Formula:
4. Solve: 3x = -4x Quadratic Formula:
1. p 2 + 4p = t 2 + 2t – 3 = 0
We can determine the number of “real number” solutions by looking at part of the quadratic formula. We will only concern ourselves with the “real” solutions. You will learn about the imaginary solutions later in your math career.
The part of the quadratic formula containing the radical is called the discriminant. Quadratic FormulaDiscriminant
1. 9x 2 – 12x + 4 = x 2 + 3x + 7 =
Workbook Page #10-28 EVEN And the ½ sheet of radicals