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Unit 2 – Quadratic, Polynomial, and Radical Equations and Inequalities. Chapter 5 – Quadratic Functions and Inequalities 5.2 – Solving Quadratic Equations by Graphing. 5.2 – Solving Quadratic Equations by Graphing. Quadratic equation – when a quadratic function is set to a value
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Unit 2 – Quadratic, Polynomial, and Radical Equations and Inequalities Chapter 5 – Quadratic Functions and Inequalities 5.2 – Solving Quadratic Equations by Graphing
5.2 – Solving Quadratic Equations by Graphing • Quadratic equation– when a quadratic function is set to a value • ax2 + bx + c = 0, where a ≠ 0 • Standard form – where a, b, and c are integers
5.2 – Solving Quadratic Equations by Graphing • Roots – solutions of a quadratic equation • One method for finding roots is to find the zeros of the function • Zeros – the x-intercepts of its graph • They are solutions because f(x) = 0 at those points
5.2 – Solving Quadratic Equations by Graphing • Example 1 • Solve x2 – 3x – 4 = 0 by graphing.
5.2 – Solving Quadratic Equations by Graphing • A quadratic equation can have one real solution, two real solutions, or no real solution.
5.2 – Solving Quadratic Equations by Graphing • Example 2 • Solve x2 – 4x = -4 by graphing.
5.2 – Solving Quadratic Equations by Graphing • Example 3 • Find two real numbers with a sum of 4 and a product of 5, or show that no such numbers exist.
5.2 – Solving Quadratic Equations by Graphing • Often exact roots cannot be found by graphing • We can estimate solutions by stating the integers between which the roots are located.
5.2 – Solving Quadratic Equations by Graphing • Example 4 • Solve x2 – 6x + 3 = 0 by graphing. If exact roots cannot be found, state the consecutive integers between which the roots are located.
5.2 – Solving Quadratic Equations by Graphing • Example 5 • The highest bridge in the U.S. is the Royal Gorge Bridge in Colorado. The deck is 1053 feet above the river. Suppose a marble is dropped over the railing from a height of 3 feet above the bridge deck. How long will it take the marble to reach the surface of the water, assuming there is no air resistance? Use the formula h(t) = -16t2 + h0, where t is time in seconds and h0 is the initial height above the water in feet.
5.2 – Solving Quadratic Equations by Graphing Example 5 (cont.) The highest bridge in the U.S. is the Royal Gorge Bridge in Colorado. The deck is 1053 feet above the river. Suppose a marble is dropped over the railing from a height of 3 feet above the bridge deck. How long will it take the marble to reach the surface of the water, assuming there is no air resistance? Use the formula h(t) = -16t2 + h0, where t is time in seconds and h0 is the initial height above the water in feet.
5.2 – Solving Quadratic Equations by Graphing HOMEWORK Page 249 #15 – 29 odd, 30 – 31, 44 – 45