The x-coordinates of the incentre of the triangle where the mid-points of the sides are (0, 1), (1, 1) and (1, 0) is
2+2
1+2
2−2
1−2
Let D(0,1), E(1,1) and F(1, 0) be the mid-points
of sides BC,CA and AB respectively of △ABC. Then, the
coordinates of the vertices are
A(1+1−0,0+1−1),B(0+1−1,1+0−1),C(0+1−1,1+1−0)
i.e. A(2,0),B(0,0),C(0,2)
Hence. the coordinates of the incentre are
2×22+2+22+22,2×22+2+22+22=(2−2,2−2)