Question 835327
The midpoint is the average of the x values and the average of the y values.
I'll do one and you can do the others.
{{{x[m]=(5+9)/2=14/2=7}}}
{{{y[m]=(8-5)/2=3/2}}}
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(7,3/2)
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{{{drawing(300,300,-5,15,-10,10,grid(1),circle(5,8,0.2),circle(9,-5,0.2),circle(7,3/2,0.3),
line(5,8,9,-5))}}}