10.3 ­ Parabolas Day 2.notebook March 27, 2017 1 10.3 ­ Parabolas Day 2.notebook March 27, 2017 10.3: Parabolas Continued Date: 3/27 Write the equations of the parabolas with the following characteristics: Ex 1: Focus: (7, 0) and Directrix: 2 10.3 ­ Parabolas Day 2.notebook March 27, 2017 Ex 2: Focus: (0, ‐25) and Directrix: 3 10.3 ­ Parabolas Day 2.notebook March 27, 2017 Ex 3: Vertex: (2, ‐3) and Focus: (2, ‐5) 4 10.3 ­ Parabolas Day 2.notebook March 27, 2017 Ex 4: Focus: (3, 2) and Directrix: 5 10.3 ­ Parabolas Day 2.notebook March 27, 2017 Ex 5: Focus: (‐3, 4) and Directrix: 6 10.3 ­ Parabolas Day 2.notebook March 27, 2017 Ex 6: The satellite dish, like the one shown at the right, is in the shape of a parabolic surface. Signals coming from a satellite strike the surface of the dish and are reflected to the focus, where the receiver is located. The satellite dish shown has a diameter of 12 feet and a depth of 2 feet. How far from the base of the dish should the receiver be placed? 7 10.3 ­ Parabolas Day 2.notebook March 27, 2017 Ex 7: The towers of the Golden Gate Bridge connecting San Francisco to Marin County are 1280 meters apart and rise 160 meters above the road. The cable between the towers has the shape of a parabola and the cable just touches the sides of the road midway between the towers. What is the height of the cable 200 meters from a tower? Round to the nearest meter. 8 10.3 ­ Parabolas Day 2.notebook March 27, 2017 Ex 8: A satellite dish in the shape of a parabolic surface has a diameter of 20 feet. If the receiver is to be placed 6 feet from the base, how deep should the dish be? 9 10.3 ­ Parabolas Day 2.notebook March 27, 2017 Homework: pg. 926 #18 – 30(e), 66, 67, and pg. 928 #12, 13, 19, 21, 26, 27 Enjoy your day off tomorrow! 10.