River Crossing (Math Exploration Quilt)
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Rik Littlefield; Hanford School  
You want to cross a river to reach a point exactly opposite where you are currently standing. Explore this problem stepbystep, encountering the following basic ideas: 1) Pythagorean theorem; 2) time = distance / speed; 3) distance = time * speed; 4) sums and differences of distances; and 5) the arcsine function for right triangles (which we didn't really need to solve the problem, just to get the angle expressed in a familiar way).  


Levels:  Middle School (68), High School (912) 
Languages:  English 
Resource Types:  Lesson Plans and Activities 
Math Topics:  Equations, Calendars/Dates/Time, Triangles and Other Polygons, Trigonometry 
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