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Midpoint Theorem in a triangle

In the figure, ABC is a triangle. D is a point on [AB] and E is a point on [AC].

Question 1

Observe the length of segments [AD], [DB], [AE] and [EC]. What does represent the point D for the segment [AB] and point E for segment [AC]?

Question 2

Observe the value of the angles <ADE and <ABC. What can you say about the lines (DE) and (BC)?

Question 3

Observe the length of [DE] and [BC]. What can you say about the length of [DE] and [BC]?

Drag points A, B and C randomly. Reflect if the observations made in Question 1 to 3 are still the same after points A, B and C are moved.

Question 4

Complete the following sentence to suggest what Midpoint Theorem is. "In △ABC, if D midpoint of [AB] and E midpoint of [AC], then ..."