Let the points of parallelogram are A(−2,1),B(−6,5)C(−10) and D(x,y)
We know that, diagonals of parallelogram bisect each other.
(2−2−1​,21+0​)=(2x−6​,2y+5​)
2−3​=2x−6​ and 21​=2y+5​⇒−3=x−6 and 1=y+5⇒x=−3+6 and y=1−5⇒x=3 and y=−4 Thus. coordinates of fourth vertex of parallelogram are (3−4)