Question 1185395
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A(7,-4)
B(a,b)
C(c,d)<br>
The coordinates of the centroid are the averages of the coordinates of the three vertices:<br>
{{{(7+a+c)/3=1}}}
{{{7+a+c=3}}}
{{{a+c=-4}}}<br>
{{{(-4+b+d)/3=2}}}
{{{-4+b+d=6}}}
{{{b+d=10}}}<br>
The coordinates of the midpoint (m,n) of BC are the averages of the coordinates of B and C:<br>
{{{m=(a+c)/2 = -4/2 = -2}}}
{{{n=(b+d)/2 = 10/2 = 5}}}<br>
ANSWER: the midpoint of BC is (m,n)=(-2,5)<br>