Finding the midpoint of a line segment
A line segment joins two coordinates on a graph. We can find the midpoint (point in the middle) in two different ways.
We could find the midpoint by drawing a graph. Just draw enough to fit the two coordinates on - I've used the coordinates (2, 2) and (4, 8) in my picture. You can sometimes just "see" the midpoint by looking at the line you've drawn. If you can't, draw in a right-angled triangle. The base of this triangle is the difference in x values and the height is the difference in y values. You can then find the middle of each of these two lines, then work back to the line segment to find the midpoint.
We could also find the midpoint using the mean (average). We can think about the midpoint as being the average of x values and average of y values. So to find the x coordinate f the midpoint, add the two x coordinates and divide by 2 (because there are two values). Then repeat for the y coordinates.