Question 214254
M is the midpoint of QR. Q has coordinates (-3,5), and M has coordinates (7,-9). Find the coordinates of R.


Step 1.  The midpoint is calculated as the average of the x-coordinates and y-coordinates between the two points. Let (x,y) be the coordinates of R.


Step 2.  x-coordinate of midpoint is found as 


{{{7=(-3+x)/2}}}

{{{2*7=-3+x}}}


{{{14+3=-3+x+3}}}


{{{x=17}}}


Step 3.  y-coordinate of midpoint is found as 


{{{-9=(5+y)/2}}}

{{{2*(-9)=5+y}}}


{{{-18-5=5+y-5}}}


{{{y=-23}}}


Step 4.  The other endpoint R is (17,-23)


I hope the above steps were helpful. 


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And good luck in your studies!


Respectfully,
Dr J