Aboat travels 26 miles up a river in the same amount of time it takes to travel 38 miles down the same river. if the current is 3 mph, what is the speed of the boat in till water?

Let the speed of the boat in still water = X

The current is 3 mph, so the speed of the boat going upstream would be x-3

Speed of the boat going down stream would be x +3

The trip upstream is 26 / x-3

The trip downstream is 38 / x+3

Set them to equal and solve for x:

26/x-3 = 38/x+3

Multiply both sides by (x+3)(x-3):

38(x-3) = 26(x+3)

Simplify:

38x - 114 = 26x+78

Subtract 26x from each side:

12x -114 = 78

Add 114 to each side:

12x = 192

Divide both sides by 12:

x = 192 / 12

x = 16

The speed is 16 miles per hour.

geometry: triangles

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call the larger triangle abc

then the smaller triangle cde is similar to abc (all angles are equal, aaa).  

ab is the side that is 36, and we wish to find de, the side corresponding to ab

area_cde = area_abc - area_cde --> area_abc / area_cde = 2

let x=length of de

ratio of areas = (ratio of sides)^2

+2+=+%2836%2fx%29%5e2+

+2+=+1296%2fx%5e2+

++x%5e2+=+1296%2f2+=+648+

25.45584

what is the answer?