如图,AB=AC=6,角B=角C=15度,则三角形ABC面积等于?

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如图,AB=AC=6,角B=角C=15度,则三角形ABC面积等于?
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如图,AB=AC=6,角B=角C=15度,则三角形ABC面积等于?
如图,AB=AC=6,角B=角C=15度,则三角形ABC面积等于?
 

如图,AB=AC=6,角B=角C=15度,则三角形ABC面积等于?
过B作BD⊥AC,交CA延长线于D,
∵∠ABC=∠C=15°,∴∠BAD=∠ABC+∠C=30°,
∴BD=1/2AB=3,
∴SΔABC=1/2AC*BD=1/2×6×3=9.