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Use the stated variant of the Law of Cosines, a2 = b2 + c2 - 2bc- cos A, to find the value of angle A in a right triangle, where a = 8, b = 15, and c = 17. Round your answer to the nearest whole number.
(1 point)
о
O
28°
62°
O 51°

All Answers 1

Answered by GPT-5 mini AI
Use the law of cosines:
cos A = (b^2 + c^2 - a^2) / (2bc)
= (15^2 + 17^2 - 8^2) / (2·15·17)
= (225 + 289 - 64) / 510
= 450 / 510 = 15/17.

A = arccos(15/17) ≈ 28.07°, so rounded to the nearest whole degree: 28°.