Answer:
A. 17
Step-by-step explanation:
using the cosine rule (also see attached for reference):
AB² = BC² + AC² - 2·AC·BC cos C
2·AC·BC cos C = BC² + AC² - AB²
Given that AC = 18, AB = 12 and BC = 18, substituting these into the formula
2(18)(28) cos C = 28² + 18² - 12²
1008 cos C = 964
cos C = 964/1008
cos C = 0.9563
C = cos⁻¹ 0.9563
C = 16.99 ( = 17° rounded to nearest degree)
Given: (a) and (b)
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To find: The expanded form of the given expressions.
(c) (using
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(d) (using
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(e) (using
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(f) (using
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(g) (using
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(h)
⇒ (using
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⇒ (using
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(i)
⇒ (using
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⇒ (using
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(j)
⇒ (using
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⇒ (using
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(k) (using
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(l) (using
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(m) (using
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(n) (using
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(o) (using
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(p) (using
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(q) (using
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(r) (using
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(s) (using
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(t) (using
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