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3 years ago

Brian drives 215 miles at an average speed. He then travels 75 more miles at a speed

Mathematics

1 answer:

Sedaia [141]3 years ago

6 0

His average speed for the first trip is 43 mph

Since Brian's average speed is x and he travels the first part for 215 miles in time t.

So, his distance d = xt

Also, the travels 75 more miles at a speed of 15 mph.

Since distance = speed time, the time he takes to cover this distance is

t' = distance/speed = 75 mi/15 mph = 5 hours

Since he covers both distances in the same time, we have that t = t' = 5 hours.

So, his average speed for the first trip x = d/t

= 215 mi/5 h

= 43 mph

His average speed for the first trip is 43 mph

Learn more about average speed here:

brainly.com/question/13605708

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3 years ago

If the length of a rectangle is 6 more than twice the width and the total perimeter is 84cm, what is the rectangle's length?

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2 years ago

Show me how to graph f(x)=3/2 x + 2

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When you move 3 up from (0,2), you get (0,5) and move 2 right which is (2,5).

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