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Đáp án:373,47 cm²
Giải thích các bước giải:
Góc A= 85 độ
Từ C kẻ đường cao CH
Ta có :CH=BC.sin B
⇒CH=40. sin 40 độ
⇒CH≈27.71cm
CH= sinA.AC ⇒AC= CH/sinA≈25,91 cm
BH= cos B . BC ≈ 30,64 cm
AH= cos A. AC ≈2,25cm
⇒AB≈32,89
SΔABC=1/2.CH.AB≈373,47 cm²
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What ...................................... Mr Ha ( live ) .......................................?
Vẽ hộ ảnh 1 người con gái đang dựa lưng vào gốc anh đào (Vì đây pé định làm ava đôi nên sẽ có người con trai nx á) Người con trai sẽ ở câu hỏi sau nha <3
Con chim nào là chim dep Nhât trong ho khuou
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