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Bell Work. When given the equation: 2x + 3 > x +5 Solve for x. Explain how you got your answer. Scale Drawings. Math notebook & pencil. Scale Drawing.
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Bell Work When given the equation: 2x + 3 > x +5 Solve for x. Explain how you got your answer.
Scale Drawings Math notebook & pencil
Scale Drawing • A drawing that shows a real object with accurate sizes except they have all been reduced or enlarged by a certain amount (called the scale).
How to Write it • The scale is shown as the length in the drawing, then a colon (":"), then the matching length on the real thing. Example: A drawing has a scale of "1:10", so anything drawn with the size of "1" would have a size of "10" in the real world, so a measurement of 150mm on the drawing would be 1500mm on the real horse.
Scale Factor • The ratio of any two corresponding lengths in two similar geometric figures is called as Scale Factor. • The ratio of the length of the scale drawing to the corresponding length of the actual object is called as Scale Factor. • A scale factor is a number used as a multiplier in scaling. • A scale factor is used to scale shapes in 1, 2, or 3 dimensions.
Scale Factors 1. Size Transformation: In size transformation, the scale factor is the ratio of expressing the amount of magnification.2. Scale Drawing: In scale drawing, the scale factor is the ratio of measurement of the drawing compared to the measurement of the original figure.3. Comparing Two Similar Geometric Figures: The scale factor when comparing two similar geometric figures, is the ratio of lengths of the corresponding sides.
Example • Find the scale factor from the larger rectangle to the smaller rectangle, if the two rectangles are similar. Choices: A. 5:1 B. 5:6 C. 6:5 D. 6:7
Solution Step 1: If we multiply the length of one side of the larger rectangle by the scale factor we get the length of the corresponding side of the smaller rectangle.Step 2: Dimension of larger rectangle × scale factor = dimension of smaller rectangleStep 3: 24 × scale factor = 20 [Substitute the values.]Step 4: Scale factor = 20/24 [Divide each side by 24.]Step 5: Scale factor = = 5:6 [Simplify.]Therefore, scale factor from the larger rectangle to the smaller rectangle is 5:6.
Scale Factor • How do you find a scale factor? • Virtual Nerd
Example • Theo is on a road trip. The next gas station on his route is 9 miles down the road. On a map with a scale of 1 inch = 3 miles, what is the distance between the two gas stations?
Example • Leslie made a scale drawing of a city park. The soccer field is 14 millimeters long in the drawing. The actual field is 98 meters long. What is the scale of the drawing?
Example • Terrence is an election officer. On election day, he travels from his home to the polling place, which appears 4 centimeters away on a map of the county. If the scale of the map is 1 centimeter = 2 kilometers, then what is the actual distance between Terrence's home and the polling place?
Dr. Noble, a marine biologist, is studying shark attacks on the coast of Lewis County. Two recent attacks took place at beaches separated by 10 inches on a map of the coastline; the beaches are 35 miles apart. What is the scale of the map?