ACT Math : How to find the midpoint of a line segment
Study concepts, example questions & explanations for ACT Math
All ACT Math Resources
Example Questions
Example Question #1 : How To Find The Midpoint Of A Line Segment
What is the coordinate of the point that is halfway between (-2, -4) and (6, 4)?
(0,2)
(2,2)
(2,0)
(3,1)
(2,0)
The midpoint formula is 
Example Question #2 : How To Find The Midpoint Of A Line Segment
What is the midpoint of MN between the points M(2, 6) and N (8, 4)?
(3, 1)
(5, 2)
(3, 5)
(5, 5)
(2, 1)
(5, 5)
The midpoint formula is equal to 
. Add the x-values together and divide them by 2, and do the same for the y-values.
x: (2 + 8) / 2 = 10 / 2 = 5
y: (6 + 4) / 2 = 10 / 2 = 5
The midpoint of MN is (5,5).
Example Question #1 : How To Find The Midpoint Of A Line Segment
In the standard coordinate plane, what is the midpoint of a line segment that goes from the point (3, 5) to the point (7, 9)?
(7, 5)
(–2, –2)
(5, 7)
(10,14)
(6,6)
(5, 7)
The midpoint formula is 
. An easy way to remember this is that finding the midpoint simply requires that you find the averageof the two x-coordinates and the average of the two y-coordinates. In this case, the two x-coordinates are 3 and 7, and the two y-coordinates are 5 and 9. If we substitute these values into the midpoint formula, we get (3 + 7/2), (5 + 9)/2, which equals (5, 7). If you got (–2, –2), you may have subtracted your x and y-coordinates instead of adding. If you got (10,14), you may have forgotten to divide your x and y-coordinates by 2. If you got (6,6), you may have found the average of x1 and y2 and x2 and y1 instead of keeping the x-coordinates together and the y-coordinates together. If you got (7, 5), you may have switched the x and y-coordinates.
Example Question #1 : How To Find The Midpoint Of A Line Segment
Find the midpoint of a line segment with endpoints (–1, 4) and (3, 6).
(3, 2)
(5, 1)
(1, 5)
(4, 5)
(1, 5)
The formula for midpoint = (x1 + x2)/2, (y1 + y2)/2. Substituting in the two x coordinates and two y coordinates from the endpoints, we get (–1 + 3)/2.
(4 + 6)/2 or (1, 5) as the midpoint.
Example Question #5 : How To Find The Midpoint Of A Line Segment
In the standard x, y coordinate plane what are the coordinates of the midpoint of a line whose endpoints are (–6, 4) and (4, –6)?
1, 1
–1, –1
–1, –1/2
1, –1
–1, 1
–1, –1
To solve this problem we use the midpoint formula. We find the average of the x and y coordinates. (–6 + 4)/2, (4 + –6)/2 = –1, –1
Example Question #6 : How To Find The Midpoint Of A Line Segment
What is the midpoint of a real number line with points at 
Method A:
To find the midpoint, draw the number line that contains points 
Then calculate the distance between the two points. In this case, the distance between 
Method B:
To find the midpoint, use the midpoint formula:
Example Question #1 : How To Find The Midpoint Of A Line Segment
Janice and Mark work in a city with neatly gridded streets. If Janice works at the intersection of 33rd Street and 7th Avenue, and Mark works at 15th Street and 5th Avenue, how many blocks will they each travel to lunch if they meet at the intersection exactly in between both offices?
Translating the intersections into points on a graph, Janice works at (33,7) and Mark works at (15,5). The midpoint of these two points is found by taking the average of the x-coordinates and the average of the y-coordinates, giving ((33+15)/2 , (5+7)/2) or (24, 6). Traveling in one direction at a time, the number of blocks from either office to 24th street is 9, and the number of blocks to 6th is 1, for a total of 10 blocks.
Example Question #1 : How To Find The Midpoint Of A Line Segment
On the real number line, what is the midpoint between 
On the number line,
We find the midpoint of this distance by dividing it by 2.
To find the midpoint, we add this value to the smaller number or subtract it from the larger number.
The midpoint value will be 
Example Question #2 : How To Find The Midpoint Of A Line Segment
What is the midpoint between 
Using the midpoint formula,
We get:
Which becomes: which becomes
Example Question #10 : How To Find The Midpoint Of A Line Segment
What is the midpoint of a line segment with endpoints 
The midpoint of a line can be found using the midpoint formula, given by:
Thus when we plug in our values we get the midpoint is
All ACT Math Resources
