SOLUTION: A boat is 8 km north and 15 km west of its starting point.How far is the boat from its starting point?

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Question 328705: A boat is 8 km north and 15 km west of its starting point.How far is the boat from its starting point?
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
the boat is 8 km north and 15 km west of its starting point.

Let its starting point = the origin of a graph.

This means that x = 0 and y = 0.

Let west be the horizontal line along the x-axis and let y = the vertical line along the y-axis.

15 km west of its starting point would be at x = 15.

8 km north of its starting point would be at y = 8

The point on the graph where the boat is located is (x,y) = (15,8).

the distance of the boat from its starting point is the hypotenuse of the right triangle formed by a horizontal line of 15 km in length and a vertical line of 8 km in length.

the length of this line is equal to the square root of 15^2 + 8^2 which makes it equal to the square root of 225 + 64 which makes it equal to the square root of 289 which makes it equal to 17 km.

a rough sketch of the graph is shown below:

                                 x
                               (0,8)                        (15,8)
                                 x                         x   x  
                                 x                     x       x  
                                 x                  x          x  
                                 x               x             x  
                                 x           x                 x  
                                 x       x                     x  
                                 x   x                         x  
 x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x x 
                               (0,0)                        (15,0)
                                 x
                                 x
                                 x
                                 x
                                 x
                                 x

coordinates are expressed as (x,y)
x is the value of the x-coordinate
y is the value of the y-coordinate