In RT △ ABC, ∠ B = 90 ° is connected to the midpoint m of AC side, and BM = cm = am is proved
prove:
Take the midpoint n of AB and connect Mn, then Mn is the median line of ⊿ ABC
∴MN//BC
∴∠ANM=∠ABC=90º
Then Mn is the vertical bisector of ab
‖ am = BM [the distance from the point on the vertical bisector to both ends of the line segment is equal]
∵AM=CM
∴BM=CM=AM
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