SOLUTION: Find the distance between the points, and find the midpoint of the line segment joining them? (9,8) and (2,1)

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Question 133211: Find the distance between the points, and find the midpoint of the line segment joining them? (9,8) and (2,1)

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
First let's find the distance


Start with the given distance formula
d=sqrt%28%28x%5B1%5D-x%5B2%5D%29%5E2%2B%28y%5B1%5D-y%5B2%5D%29%5E2%29 where is the first point and is the second point

d=sqrt%28%289-2%29%5E2%2B%288-1%29%5E2%29 Plug in x%5B1%5D=9, x%5B2%5D=2, y%5B1%5D=8, y%5B2%5D=1

d=sqrt%28%287%29%5E2%2B%287%29%5E2%29 Evaluate 9-2 to get 7. Evaluate 8-1 to get 7.

d=sqrt%2849%2B49%29 Square each value

d=sqrt%2898%29 Add

d=7%2Asqrt%282%29 Simplify the square root (note: If you need help with simplifying the square root, check out this solver)


So the distance approximates to

d=9.89949493661167

which rounds to
9.89949

So the distance between (9,8) and (2,1) is approximately 9.89949 units







Now let's find the midpoint


In order to find the midpoint between the points (9,8) and (2,1), we need to average each corresponding coordinate. In other words, we need to add up the corresponding coordinates and divide the sum by 2.


So lets find the averages between the two points



To find , average the x-coordinates between the two points
x%5Bmid%5D=%289%2B2%29%2F2=%2811%29%2F2=5.5


So the x-coordinate of the midpoint is 5.5 (i.e. x=5.5)
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To find , average the y-coordinates between the two points
y%5Bmid%5D=%288%2B1%29%2F2=%289%29%2F2=4.5


So the y-coordinate of the midpoint is 4.5 (i.e. y=4.5)
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Answer:
Since the coordinates of the midpoint are x=5.5, y=4.5, this means the midpoint is (5.5,4.5)

Check:
Here is a graph to visually see the answer
Graph of the line segment with the endpoints (9,8) and (2,1) with the midpoint (5.5,4.5)



We could visually verify our answer if we simply draw right triangles from each point like this:


Here we can see that the two triangles are congruent (they both have a right angle and equal leg lengths), so our answer is verified.