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What would be the length of BC?

What would be the length of BC?-example-1

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Answer:

a. 33.01

Explanation:

Since we don't know whether or not triangle ABC is a right angle and we have an angle sandwiched between two sides, we can find the length of BC using the Law of Cosines, which is given by:

a^2 = b^2 + c^2 - 2bc * cos A

b^2 = a^2 + c^2 - 2ac * cos B

c^2 = a^2 + b^2 - 2ab * cos C

We can call let A represent angle A, c represent side AB, let b represent side AC, and let a represent side BC.

Thus, we can find the length of a (i.e., BC) using the first equation from the law of cosines:

Step 1: Plug in 91 for A, 28 for c, and 17 for b and simplify:

a^2 = 17^2 + 28^2 - 2(17)(28) * cos (91)

a^2 = 1073 - 952 * cos (91)

Step 2: Take the square root of both sides to solve for a (i.e., the length of side BC) and round:

Note that since we want a positive answer, we can already ignore the negative answer to the square root:

√(a^2) = √(1073 - 952 * cos (91))

a = 33.00931219

a = 33.01

Thus, side BC is about 33.01 units long.

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