1 5.4 – Completing the SquareObjectives: Use completing the square to solve a quadratic equation. Use the vertex form of a quadratic function to locate the axis of symmetry of its graph. Standard: N. Solve quadratic equations symbolically and graphically
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6 Example 1
7 Example 1 c and d c. x2 – 7x d. x2 + 16x The coefficient of x is -7½ (-7) = Thus the perfect square trinomial is d. x2 + 16x The coefficient of x is 16 ½ (16) = 8 (8)2 = 64 Thus the perfect square trinomial is
8 Solving Equations by Completing the SquareSTEPS: Make sure A = 1. Bring the C to the Zero side. Complete the Square -“ take ½ of B and Square It.” Add the completed square to each side. Express the left side using perfect square notation. Solve the equation.
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10 Example 2a
11 Example 2b
12 Example 2c
13 Practice – Completing the Square
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19 Homework: packet sec. 5-4