1. Math I 01-17-13 UNIT QUESTION: What do solutions of equations represent? Standard: MM1A3 Today’s Question: How do we solve quadratic equations algebraically? Standard: MM1A3.a.

2. Lesson 2.5 - Solving Quadratic Equations in Factored Form y = x 2 + 5x + 6 y = (x + 3)(x + 2)

3. Notes - Solving Quadratic Equations in Factored Form If ab = 0, then a = 0 or b = 0 If the product of two factors is zero, then at least one of the factors must be zero. 3 * 0 = 00 * 3 = 00 * 0 = 0

4. Notes - Solving Quadratic Equations in Factored Form (x – 2)(x + 3) = 0

5. Ex. 1: Solve the equation x 2 + x – 6 = 0 STEP 1: Factor x-2= 0 and x+3 = 0 STEP 3: Solve for x. x-2= 0 x = 2 x+3 = 0 x=-3 STEP 4: Check your answers. x 2 + x – 6 = 0 4 + 2 - 6 = 0 0 = 0 x 2 + x – 6 = 0 9 - 3 - 6 = 0 0 = 0 (x – 2) and (x+3) STEP 2: Set each factor equal to 0.

6. Solve (Find the x-intercepts) 2) (x – 1)(x – 3) = 0 3) x(x – 2) = 0 4) (3x +5)(2x + 7) = 0 5) 6) (x + 5) 2 = 0 (x – 6) 2 = 0

7. 7: Solve the equation x 2 + 7x + 10 = 0 STEP 1: Factor X + 2 = 0 and x + 5 = 0 STEP 3: Solve for x. X + 2= 0 x = -2 X + 5 = 0 x = -5 STEP 4: Check your answers. x 2 + 7x + 10 = 0 0 = 0 (x + 2) and (x + 5) STEP 2: Set each factor equal to 0.

8. TRY THESE: 8) x 2 + 5x + 6 = 09) x 2 – 2x – 8 = 0

9. Extension x feet (x-4) feet a)Find an expression for the area. b)If the area is equal to 5 square feet, find x. x 2 – 4x x = 5

10. Class work Practice Worksheet