Question

1. The midpoint of Line Segment AB is (2, -9). The coordinates of one endpoint are A (4, 10). Find the coordinates of endpoint B.

Answer 1

Given:-
midpoint of AB($x_{m}, y_{m}$) = (2,-9) ; A($x_{1}, y_{1}$)
let points of B be ($x_{2}, y_{2}$)

midpoint formula :- $x_{m} = \frac{ x_{2} - x_{1} }{2}$  and $y_{m} = \frac{ y_{2} - y_{1} }{2}$

∴ $x_{2} = 2 x_{m} + x_{1} = 2*2 + 4 = 8$
   $y_{2} = 2y_{m} + y_{1} = 2*(-9) + 10 = -8$

Ans = B(8,-8)