7. In △ABC, BC = 10cm, ∠ABC =35∘and ∠BAC =80∘
(a) Find AC.
(b) find the area of △ABC.
(Give your answer correct to 2 decimal places.)
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2007-12-07 1:40 am
回答 (2)
2007-12-07 5:41 am
✔ 最佳答案
根據 sin A/a=sin B/b=sin C/csin80∘/10=sin35∘/ AC
AC=5.82
根據 Area of triangle=0.5*a*b*sin C
area of △ABC=0.5*10*5.82*sin(180-35-80)
area of △ABC=26.39
2007-12-06 21:42:40 補充：
AC=5.82cmarea of △ABC=26.39cm
2007-12-06 21:43:29 補充：
area of △ABC=26.39cm^2
2007-12-07 2:01 am
7 a. AC/sin35∘= 10/sin80∘
AC=5.82cm
b the area of △ABC: (0.5)(5.82)(10)sin(180∘-80∘-35∘)
=26.4cm^2
AC=5.82cm
b the area of △ABC: (0.5)(5.82)(10)sin(180∘-80∘-35∘)
=26.4cm^2
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