M(2.1, 5.7) is the midpoint of , in which A is the

Question

point (1.7, 2.3). Find the coordinates of B.

Answer 1

let B be (x,y)
then (x+1.7)/2 = 2.1
x+1.7 = 4.2
x = 2.5

find y in the same way, and you have B