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Blababa [14]
4 years ago
8

A steamer going downstream traveled the distance between two ports in 3 hours. The return trip took 3 hours 40 minutes. Find the

speed of the water current if the speed of the steamer in still water is 18 mph.
Mathematics
1 answer:
lapo4ka [179]4 years ago
6 0

Answer:

1.8 mph

Step-by-step explanation:

Speed of the steamer in still water is 18 mph.

Speed of the current = x mph.

1. The steamer going downstream traveled the distance between two ports in 3 hours. Traveling downstream the current "helps" the steamer, then the speed is 18 + x mph.

The distance traveled downstream = 3(18 + x) miles.

2. The steamer going upstream traveled the distance between two ports in 3 hours 40 minutes that is 3\frac{2}{3} hours. Traveling upstream the current "interferes" the steamer, then the speed is 18 - x mph.

The distance traveled upstream 3\dfrac{2}{3}(18-x) miles.

3. The distances are the same, so

3(18+x)=3\dfrac{2}{3}(18-x)

Solve this equation:

3(18+x)=\dfrac{11}{3}(18-x)\\ \\9(18+x)=11(18-x)\\ \\162+9x=198-11x\\ \\9x+11x=198-162\\ \\20x=36\\ \\x=1.8\ mph

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Answer:

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Step-by-step explanation:

To solve this problem we need to factorize 4n^2 + 28n +49 as shown below

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we can validate this by expanding it

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4 years ago
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hichkok12 [17]

I'm assuming you are finding the equation of the line of Line J

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For example:

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Since you know the slope is 3, the perpendicular line's slope is -\frac{1}{3}.  Plug this into the equation

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sp2606 [1]

Answer:

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Step-by-step explanation:

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