Question

The midpoint of AB is M(-2, 4). The coordinates of A are (-1, 5), what are the coordinates of B?

Answer 1

Answer: B : (-3,3)

Explanation:

We are given the coordinates of the Midpoint and A and we must find B. In order to solve for the coordinates of B, we must use the Midpoint formula and plug in the information we are given.

Midpoint Formula :
`(x1+x2)/2 , (y1+y2)/2`

Let's make the coordinates of A = (x1,y1) and we are solving for B = (x2,y2). Now using the formula lets plug in what we know to find B's coordinates:

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

`(5+y)/2=4`

Now simplify :

`-1+x2=-4\\x2=-3`

`5+y=8\\y=3`

Now write it as a coordinate pair :
`(-3,3)`, and there's your answer.

That's it!