How to Find the Midpoint of a Line Segment
In order to find the midpoint of a line segment, you first have to understand that it's the point located on the exact midpoint of the 2 endpoints, so it's the average of the endpoints. To use the midpoint formula, add the x-coordinates of the endpoints and divide the result by 2. Then, add the y-coordinates of the endpoints and divide them by 2. Once you know the coordinates of the endpoints, you can plug them into the formula and solve.
Understand the midpoint. The midpoint of a line segment is the point that is located on the exact midpoint of the two endpoints. Therefore, it's the average of the two endpoints, which is the average of the two x-coordinates and the two y-coordinates. Learn the midpoint formula. The midpoint formula can be used by adding the x-coordinates of the two endpoints and dividing the result by two and then adding the y-coordinates of the endpoints and dividing them by two. This is how you will find the average of the x and y coordinates of the endpoints. This is the formula: [(x 1 + x 2 )/2,( y 1 + y 2 )/2] Locate the coordinates of the endpoints. You can't use the midpoint formula without knowing the x and y-coordinates of the endpoints. In this example, you want to find the midpoint, point O, which is between the two endpoints M (5,4) and N (3,-4). Therefore, (x 1 , y 1 ) = (5, 4) and (x 2 , y 2 ) = (3, -4). Note that either pair of coordinates can serve as (x 1 , y 1 ) or (x 2 , y 2 ) -- since you'll just be adding the coordinates and dividing by two, it doesn't matter which pair is first. Plug the corresponding coordinates into the formula. Now that you know the coordinates of the endpoints, you can plug them into the formula. Here's how you do it: [(5 + 3)/2, (4 + -4)/2] Solve. Once you've plugged the appropriate coordinates into the formula, all you have to do is the simple arithmetic that will give you the midpoint of the two line segments. Here's how you do it: [(5 + 3)/2, (4 + -4)/2] = [(8/2), (0/2)] = (4, 0) The midpoint of the endpoints (5,4) and (3, -4) is (4,0). Find a vertical or horizontal line. Before you can use this method, you'll need to know how to locate a vertical or horizontal line. Here's how to spot it: A line is horizontal if the two y-coordinates of the endpoints are equal. For example, the line segment with the endpoints (-3, 4) and (5, 4) is horizontal. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/f\/f1\/Find-the-Midpoint-of-a-Line-Segment-Step-6Bullet1-Version-2.jpg\/v4-460px-Find-the-Midpoint-of-a-Line-Segment-Step-6Bullet1-Version-2.jpg","bigUrl":"\/images\/thumb\/f\/f1\/Find-the-Midpoint-of-a-Line-Segment-Step-6Bullet1-Version-2.jpg\/aid1628172-v4-728px-Find-the-Midpoint-of-a-Line-Segment-Step-6Bullet1-Version-2.jpg","smallWidth":460,"smallHeight":345,"bigWidth":"728","bigHeight":"546","licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/3.0\/\">Creative Commons<\/a><br>\n<\/p><p><br \/>\n<\/p><\/div>"} A line is vertical if the two x-coordinates of the endpoints are equal. For example, the line segment with the endpoints (2, 0) and (2, 3) is vertical. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/9\/9b\/Find-the-Midpoint-of-a-Line-Segment-Step-6Bullet2-Version-2.jpg\/v4-460px-Find-the-Midpoint-of-a-Line-Segment-Step-6Bullet2-Version-2.jpg","bigUrl":"\/images\/thumb\/9\/9b\/Find-the-Midpoint-of-a-Line-Segment-Step-6Bullet2-Version-2.jpg\/aid1628172-v4-728px-Find-the-Midpoint-of-a-Line-Segment-Step-6Bullet2-Version-2.jpg","smallWidth":460,"smallHeight":345,"bigWidth":"728","bigHeight":"546","licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/3.0\/\">Creative Commons<\/a><br>\n<\/p><p><br \/>\n<\/p><\/div>"} Find the length of the segment. You can easily find the length of the segment just by counting how many horizontal spaces it takes up if it's horizontal, and counting how many vertical spaces it takes up if it's vertical. Here's how to do it: The horizontal line segment with the end points (-3, 4) and (5, 4) is 8 units long. You can find this by counting the spaces it takes up or by adding the absolute values of the x-coordinates: |-3| + |5| = 8 {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/5\/53\/Find-the-Midpoint-of-a-Line-Segment-Step-7Bullet1-Version-2.jpg\/v4-460px-Find-the-Midpoint-of-a-Line-Segment-Step-7Bullet1-Version-2.jpg","bigUrl":"\/images\/thumb\/5\/53\/Find-the-Midpoint-of-a-Line-Segment-Step-7Bullet1-Version-2.jpg\/aid1628172-v4-728px-Find-the-Midpoint-of-a-Line-Segment-Step-7Bullet1-Version-2.jpg","smallWidth":460,"smallHeight":345,"bigWidth":"728","bigHeight":"546","licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/3.0\/\">Creative Commons<\/a><br>\n<\/p><p><br \/>\n<\/p><\/div>"} The vertical line segment with the end points (2, 0) and (2, 3) is 3 units long. You can find this by counting the spaces it takes up or by adding the absolute values of the y-coordinates: |0| + |3| = 3 {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/6\/6e\/Find-the-Midpoint-of-a-Line-Segment-Step-7Bullet2-Version-2.jpg\/v4-460px-Find-the-Midpoint-of-a-Line-Segment-Step-7Bullet2-Version-2.jpg","bigUrl":"\/images\/thumb\/6\/6e\/Find-the-Midpoint-of-a-Line-Segment-Step-7Bullet2-Version-2.jpg\/aid1628172-v4-728px-Find-the-Midpoint-of-a-Line-Segment-Step-7Bullet2-Version-2.jpg","smallWidth":460,"smallHeight":345,"bigWidth":"728","bigHeight":"546","licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/3.0\/\">Creative Commons<\/a><br>\n<\/p><p><br \/>\n<\/p><\/div>"} Divide the length of the segment by two. Now that you know the length of the line segment, you can divide it by two. 8/2 = 4 {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/8\/8f\/Find-the-Midpoint-of-a-Line-Segment-Step-8Bullet1-Version-2.jpg\/v4-460px-Find-the-Midpoint-of-a-Line-Segment-Step-8Bullet1-Version-2.jpg","bigUrl":"\/images\/thumb\/8\/8f\/Find-the-Midpoint-of-a-Line-Segment-Step-8Bullet1-Version-2.jpg\/aid1628172-v4-728px-Find-the-Midpoint-of-a-Line-Segment-Step-8Bullet1-Version-2.jpg","smallWidth":460,"smallHeight":345,"bigWidth":"728","bigHeight":"546","licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/3.0\/\">Creative Commons<\/a><br>\n<\/p><p><br \/>\n<\/p><\/div>"} 3/2 = 1.5 {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/9\/92\/Find-the-Midpoint-of-a-Line-Segment-Step-8Bullet2-Version-2.jpg\/v4-460px-Find-the-Midpoint-of-a-Line-Segment-Step-8Bullet2-Version-2.jpg","bigUrl":"\/images\/thumb\/9\/92\/Find-the-Midpoint-of-a-Line-Segment-Step-8Bullet2-Version-2.jpg\/aid1628172-v4-728px-Find-the-Midpoint-of-a-Line-Segment-Step-8Bullet2-Version-2.jpg","smallWidth":460,"smallHeight":345,"bigWidth":"728","bigHeight":"546","licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/3.0\/\">Creative Commons<\/a><br>\n<\/p><p><br \/>\n<\/p><\/div>"} Count that value from either of the endpoints. This is the last step to finding the endpoint of the line segment. Here's how you do it: To find the midpoint of the points (-3, 4) and (5, 4), just shift over 4 units either from the left or right to reach the middle of the segment. (-3, 4) shifted over 4 x-coordinates is (1, 4). You won't need to change the y-coordinates since you know the midpoint will be on the same y-coordinate as the endpoints. The midpoint of (-3, 4) and (5, 4) is (1, 4). {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/8\/88\/Find-the-Midpoint-of-a-Line-Segment-Step-9Bullet1-Version-2.jpg\/v4-460px-Find-the-Midpoint-of-a-Line-Segment-Step-9Bullet1-Version-2.jpg","bigUrl":"\/images\/thumb\/8\/88\/Find-the-Midpoint-of-a-Line-Segment-Step-9Bullet1-Version-2.jpg\/aid1628172-v4-728px-Find-the-Midpoint-of-a-Line-Segment-Step-9Bullet1-Version-2.jpg","smallWidth":460,"smallHeight":345,"bigWidth":"728","bigHeight":"546","licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/3.0\/\">Creative Commons<\/a><br>\n<\/p><p><br \/>\n<\/p><\/div>"} To find the midpoint of the points (2, 0) and (2, 3), just shift over 1.5 units either from the top or bottom to reach the middle of the segment. (2, 0) shifted up 1.5 y-coordinates is (2, 1.5). You won't need to change the x-coordinates since you know the midpoint will be on the same x-coordinate as the endpoints. The midpoint of (2, 0) and (2, 3) is (2, 1.5). {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/7\/79\/Find-the-Midpoint-of-a-Line-Segment-Step-9Bullet2-Version-2.jpg\/v4-460px-Find-the-Midpoint-of-a-Line-Segment-Step-9Bullet2-Version-2.jpg","bigUrl":"\/images\/thumb\/7\/79\/Find-the-Midpoint-of-a-Line-Segment-Step-9Bullet2-Version-2.jpg\/aid1628172-v4-728px-Find-the-Midpoint-of-a-Line-Segment-Step-9Bullet2-Version-2.jpg","smallWidth":460,"smallHeight":345,"bigWidth":"728","bigHeight":"546","licensing":"<div class=\"mw-parser-output\"><p>License: <a target=\"_blank\" rel=\"nofollow noreferrer noopener\" class=\"external text\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/3.0\/\">Creative Commons<\/a><br>\n<\/p><p><br \/>\n<\/p><\/div>"} 
Understand the midpoint. Learn the midpoint formula. Locate the coordinates of the endpoints. Plug the corresponding coordinates into the formula. Solve. Find a vertical or horizontal line. Find the length of the segment. Divide the length of the segment by two. Count that value from either of the endpoints. 