Difficulty: Easy
Correct Answer: 9 cm
Explanation:
Introduction / Context:The centroid G divides each median in the ratio 2:1, counted from the vertex. This invariant allows direct recovery of the total median length when one centroid segment is known.
Given Data / Assumptions:
Concept / Approach:By definition, BG : GE = 2 : 1 along median BE. Therefore BE = BG + GE = BG + (BG/2) = 3BG/2.
Step-by-Step Solution:BE = (3/2) * BG = (3/2) * 6 = 9 cm.
Verification / Alternative check:Compute GE = 3 cm; 6 + 3 = 9, matching BE.
Why Other Options Are Wrong:7, 8, 10 cm contradict the fixed 2:1 centroid division.
Common Pitfalls:Accidentally using 1:2 instead of 2:1 from the vertex.
Final Answer:9 cm
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