Question

If M=(2,5) is the midpoint of AB, and A=(0,-1), then the coordinates of B are _____.

A. (4, 11)

B. (1, 3)

C. (-2, -7)

D. (1, -2)

Answer 1

The point M(Mx, My) is mid-point of AB with A(Ax, Ay) and B(Bx, By).

=> 2*Mx = Ax + Bx => 2*2 = 0 + Bx => Bx = 4

=> 2*My = Ay + By => 2*(5) = -1 + By => By = 11

=> B(4, 11)

=> Option A is correct

Hope this helps!

:)