The midpoint of two coordinates is the point that’s exactly halfway between the two points, or the average of the two points. Instead of trying to visually determine the halfway point of a steep line drawn on a coordinate plane, you can use the midpoint formula. The midpoint formula -- [(x1 + x2)/2, (y1 + y2)/2] -- determines the coordinates of the midpoint between any two endpoints (x1, y1) and (x2, y2). The first part of the formula calculates the average x-coordinate of the endpoints, and the second part calculates the average y-coordinate of the endpoints.
To use an easier method to find the midpoint of a horizontal or vertical line drawn between two points on a plane, count the number of units on the respective x- or y-axis between the two points and divide by 2.
Input any two coordinates into the midpoint formula. For this example, use the coordinates (5, 6) and (1, 2). This yields the following: [(5 +1)/2, (6 + 2)/2].
Add 5 and 1, which equals 6.
Divide 6 by 2, which equals 3. This is the average x-coordinate of the endpoints.
Add 6 and 2, which equals 8.
Divide 8 by 2, which equals 4. This is the average y-coordinate of the endpoints.
Write the x- and y-coordinates as an ordered pair, which equals (3, 4). This is the midpoint of (5, 6) and (1, 2).
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