✔ 最佳答案
Method 1:
a/sin(A) = c/sin(C) (sine law)
24.2/sin(A) = 18.3/sin(44.6°)
sin(A) = sin(44.6°) × (24.2/18.3)
sin(A) = 0.9285
A = 68.2°, (180 - 68.2)°
A = 68.2°, 111.8°
Two triangles can be drawn because the sum of interior angles does not exceed 180° for each value of A.
The answer: 2
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Method 2:
c² = a² + b² - 2 a b cosC (cosine law)
18.3² = 24.2² + b² - 2 × 24.2 × b × cos(44.6°)
b² - 34.462b + 250.75 = 0
b = [34.462 ± √(34.462² - 4×250.75)]/2
b = 10.4, 24.0
Two triangles can be drawn because there are two positive values for b.
The answer: 2