Building Bridges / using geometry in Bulding Bridge Beam, arch, truss, and suspension are all types of bridges. The type chosen for a specific - amid track's. span depends on many factors, including the length of the bridge and how it handles tension and compression. What mathematical concepts are involved in the complexities of building bridges? 1. The span of a bridge is the length of the bridge between supports. Find each distance. a. A footbridge has a span of 54 feet. A sign is to be placed exactly halfway across the bridge. How far will the center of the sign be from each end of the bridge? b. A beam bridge has a total length of 168 yards. The bridge is supported at both ends and has three additional supports in the water What is the span between any two consecutive supports? C. A suspension bridge has two support towers. Each tower is 1 152 feet from the end of the bridge. The total length of the bridge is 4036 feet. What is the span between the towers? d. An arch bridge crosses a river. The bridge is supported at each end and has seven additional supports in the water. The span of each arch is 86 meters. What is the distance across the river? 22. The diagram to the right shows a truss bridge. In the diagram, each unit represents 20 meters. a. What is the length of the bridge from point of to point D? B MM b. Are the segments AE and BC congruent? AB and CD ? 10 12 14 c. What is the midpoint of EC? d. What is the perimeter of triangle ABF?Finding the Area and Perimeter of a Track How can you use formulas you already know to find the area and perimeter of a composite figure? The six-lane track shown is made up of a rectangle and two semicircles. Each lane is 1.2 meters wide 36.5m 16.5 m 85.0 m In the straightaways, each lane is a rectangle. Explain two methods for finding the total area of the six lanes in one of the straightaways. What is the total area of the six lanes in one of the straightaways? 2- What is the perimeter of one of the straightaways? Is the relationship between the perimeter of one lane in a straightaway and the rectangle made up of the six lanes of one of the straightaways the same relationship as between their areas? Explain.3- It takes 30 minutes to mow 900 square meters. How many minutes will it take you to mow the interior of the track. Use 3. 14 for a and round your answer to the nearest minute. 4- You are painting the lane lines for the track. Each gallon of paint covers a line 50 meters long. How many gallons of paint will you need to paint all the lane lines? 5. You walk around the perimeter of the entire track. Your friend walks around the perimeter of the interior of the track. How much farther do you walk than your friend? Use 3.14 for a and round your answer to the nearest hundredth. Explain your reasoning. 5