Midsegment of a Triangle
A line segment joining the midpoints of two sides of a triangle
A triangle has 3 possible midsegments.
Drag the orange dots on each vertex
to reshape the triangle.
Notice the behavior of the midsegment line.
- The midsegment is always parallel to the third side of the triangle.
In the figure above, drag any point around and convince yourself that this is always true.
- The midsegment is always half the length of the third side. In the figure above, drag point A around.
Notice the midsegment length never changes because the side BC never changes.
- A triangle has three possible midsegments, depending on which pair of sides is initially joined.
See Constructing the midsegment of a triangle with ruler and straightedge.
Other triangle topics
Perimeter / Area
Congruence and Similarity
Triangle quizzes and exercises
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