Question 322088
Use the midpoint formula, it's pretty straightforward.
{{{xm=(x1+x2)/2=(-5-3)/2=-8/2=-4}}}
{{{ym=(y1+y2)/2=(3-7)/2=-4/2=-2}}}
(-4,-2)
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{{{drawing(300,300,-10,4,-10,4, circle(-5,3,.4),circle(-3,-7,.4),circle(-4,-2,.2),blue(line(-5,3,-3,-7)),grid(1),graph(300,300,-10,4,-10,4,0))}}}