Midpoint of a line segment

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To find the midpoint of a line segment on the coordinate system, simply take the average of the x-coordinates and the average of the y-coordinates.

Let (x1 , y1) and (x2 , y2) represent the endpoints of a line segment.

Therefore, the formula to get the midpoint is: [(x1 + x2) ÷ 2 , (y1 + y2) ÷ 2]

A couple of examples showing how to find the midpoint of a line segment

Example #1:

Graph (2, 4) and (4, 8) and find the midpoint

[(x1 + x2) ÷ 2 , (y1 + y2) ÷ 2] = [(2 + 4) ÷ 2, (4 + 8)÷ 2]

[(x1 + x2) ÷ 2 , (y1 + y2) ÷ 2] = (6 ÷ 2, 12 ÷ 2)

[(x1 + x2) ÷ 2 , (y1 + y2) ÷ 2] = (3, 6)

The graph is shown below.

Midpoint


Example #2:

Graph (-4, 2) and (0, 6) and find the midpoint.

[(x1 + x2) ÷ 2 , (y1 + y2) ÷ 2] = [(-4 + 0) ÷ 2, (2 + 6)÷ 2]

[(x1 + x2) ÷ 2 , (y1 + y2) ÷ 2] = (-4 ÷ 2, 8 ÷ 2)

[(x1 + x2) ÷ 2 , (y1 + y2) ÷ 2] = (-2, 4)

The graph is shown below:

Midpoint


Example #3:

Using (5, -5) and (-1, 1), find the midpoint.

[(x1 + x2) ÷ 2 , (y1 + y2) ÷ 2] = [(5 + -1) ÷ 2, (-5 + 1)÷ 2]

[(x1 + x2) ÷ 2 , (y1 + y2) ÷ 2] = (4 ÷ 2, -4 ÷ 2)

[(x1 + x2) ÷ 2 , (y1 + y2) ÷ 2] = (2, -2)

Example #4:

Using (12, 0) and (-12, 2), find the midpoint.

[(x1 + x2) ÷ 2 , (y1 + y2) ÷ 2] = [(12 + -12) ÷ 2, (0 + 2)÷ 2]

[(x1 + x2) ÷ 2 , (y1 + y2) ÷ 2] = (0 ÷ 2, 2 ÷ 2)

[(x1 + x2) ÷ 2 , (y1 + y2) ÷ 2] = (0, 1)