Answer:
EF = 6m.
Step-by-step explanation:
Given that:
1) All the edges of the pyramid in the model have length 12m.
So, AB = 12m
2) E is the middle of AT, F is the middle of BT
So, EF is a line segment connecting the midpoints of ΔATB
So, by applying The Triangle Mid-segment Theorem
EF // AB and EF = 0.5 AB
So, EF = 0.5 AB = 0.5 * 12 = 6m
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The Triangle Mid-segment Theorem:
The line segment connecting the midpoints of any two sides of a triangle has the following properties:
1) The line segment will be parallel to the third side.
2) The length of the line segment will be a half of the length of the third side.