Question

The midpoint of AB is (1.2). The coordinates of A are (-3, 6) Find the coordinates of B.

Answer 1

Answer: coordinates of B are (5,-2)

Explanation:

let B be (x2,y2)

x1 = -3 y1 = 6

x = 1

y = 2

so

x = (x2 + x1)/2

1 = (x2+(-3))/2

or, 2 = x2 - 3

so, x2 = 5

now

y = (y2+y1)/2

or, 2 = (y2 + 6)/2

or, 4 = y2 + 6

so, y2 = -2