Question

The centroid of triangle is the point (1,4) if its two vertices are (4,-3) and (-9,7) then find the third vertex

Answer 1

centroid of triangle is (x1+x2+x3/3,y1+ y2+ y3+/3)
given x1 is 4 and x2 is -9 centroids is 1
so 4+(-9)+x3/3=1
. x3=8

similarly y1+y2+y3/3=4
-3+7+y3/3=4
4+y3=12
y3=8

so the third vertex is (8,8)