Quadratic Formula
Table of Contents 46: Warm-Up, Guided Practice 47: How Do I Use the Quadratic Formula to Factor Trinomials?
Warm-Up Solve for the roots: 1. x2 – 9 = 0 2. -x2 + 4 = 3
Warm-Up Answers Solve for the roots: 1. x2 – 9 = 0 2. -x2 + 4 = 3 + 9 ___________ ___________ - 4 - 4 x2 = 9 ___ -1 -x2 = -1 ___ -1 x = 3 x2 = 1 Roots: (3, 0) x = 1 (-3, 0) Roots: (1, 0) (-1, 0)
Learning Intention/Success Criteria LI: We are learning to factor quadratics with the quadratic formula SC: I know how to -simplify square roots -memorize the quadratic formula -locate solutions by using the quadratic formula -use integer operations -substitute values into an equation
EQ: How Do I Factor Quadratics Using Completing the Square? 5/11/2019
Do the quad solve video
The formula for the roots of a quadratic equation Quadratic Formula The formula for the roots of a quadratic equation
Example 1: Solve for the roots: 2x2 + 3x – 9 = 0 A: B: C: 2 3 -9
(-3, 0) Roots:
Guided Practice 1 Use the quadratic formula to solve the equation: 2x2 – 11x + 12 = 0
Guided Practice 1 Use the quadratic formula to solve the equation: 2x2 – 11x + 12 = 0 Roots: (4, 0) (1.5, 0)
Guided Practice 2 Use the quadratic formula to solve the equation: x2 – 4x + 3 = 0
Guided Practice 2 Use the quadratic formula to solve the equation: x2 – 4x + 3 = 0 Roots: (3, 0) (1, 0)
Example 2: Solve for the roots: x2 + 8x – 1 = 0 A: B: C: 1 8 -1
Roots: (0.12, 0) (-8.12, 0)
Guided Practice 3 Use the quadratic formula to solve the equation: 5x2 – x – 2 = 0
Guided Practice 3 Use the quadratic formula to solve the equation: 5x2 – x – 2 = 0 Roots: (0.74, 0) (-0.54, 0)
Guided Practice 4 Use the quadratic formula to solve the equation: 2x2 – 3x – 6 = 0
Guided Practice 4 Use the quadratic formula to solve the equation: 2x2 – 3x – 6 = 0 Roots: (2.64, 0) (-1.13, 0)