A motorboat takes 4 hours to travel 192 kilometers going upstream. The return trip takes 3 hours going downstream.

- What is the rate of the boat in still water?
- What is the rate of the current?

Step-by-step explanation:

let b be boat velocity

let c be current velocity

(b - c)4 = 192

(b + c)3 = 192

(b - c)4 = (b + c)3

4b - 4c = 3b + 3c

        b = 7c

(7c - c)4 = 192

    (6c)4 = 192

      24c = 192

          c = 8 km/hr

b = 7(8) = 56 km/hr

step-by-step explanation:

for the friend request.

when a figure, such as triangle (xyz) is reflected over the line y = x to create x'y'z' the x-coordinates and y-coordinates of the original image (pre-image) will be reversed for the image. (e.g., (x, y) > (y, x)) this means that the pre-image position of the x- and y-coordinates switch places which in turn provides a mirror like image of the original xyz.  

i notice that when i draw a line segment from x to x', that the points are parallel from each other -- they are exactly across from each other and do not intersect with any other points.  

yes, think i would see the same characteristic if you drew the line segment connecting y with the reflecting line and then y' with the reflecting line because of the essence of reflections. because it is a mirror image, each point was effected the same way which leads me to conclude that they same would apply to y and y'.