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3 years ago

7

West of a city, a certain eastbound route is straight and makes a steep descent toward the city. The highway has a 14% grade, wh

ich means that its slope is − 14 100 . Driving on this road, you notice from elevation signs that you have descended a distance of 1000 ft. What is the change in your horizontal distance in miles

1 answer:

vova2212 [387]3 years ago

6 0

Answer:

1.35 miles

Explanation:

Since the slope is 14% grade = -14/100. This is a negative slope.

The distance of 1000 ft descended is a vertical descent, so assuming our initial position is 0, and Δx is the change in horizontal distance.

tanθ = -14/100 = (0 - 1000)/Δx = - 1000)/Δx

-14/100 = - 1000)/Δx

Δx = -1000 × -100/14= 7142.86 ft

5280 ft = 1 mile

7142.86 ft = 7142.86/5280 miles = 1.353 miles ≅ 1.35 miles

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The graph of V versus r can be found in attachment.

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