Question

In the standard (x,y) coordinate plane, the midpoint of AB is (3,–4) and A is located at (2,–3), what is the coordinate of B?

Answer 1

If `"M"` is the midpoint of `"AB"`
then `Delta y (A" to " M) = Delta y (M " to " B)`
and `Delta x(A" to " M) = Delta x (M " to " B)`

Since `A` is located at `(2,-3)`
and `M` is located at `(3,-4)`

`Delta y (A" to " M) = (-4)-(-3) = -1`
and
`Delta x (A" to " M) = 3-2 = 1`

`B` is located at `(M_x+Delta x, M_y+Delta y)`
`=(3+1,-4+(-1))`
`=(4,-5)`