Here’s an example:
I have a line segment and the three points on it are D (the first endpoint), E (the midpoint), and F (the last endpoint). Also:
. . .DE = x
. . .EF = 3x - 1
. . .DF = 2x + 4
I wrote the equation as:
. . .2x + 4 = x + 3x - 1
I worked it out as:
. . .2x + 4 = x + 3x - 1
. . .2x + 4 = 4x - 1
. . .4 = 2x - 1
. . .5 = 2x
. . .x = 2.5
