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What is the value of a?

Enter your answer in the box.

Round only your final answer to the nearest whole number.

What is the value of a? Enter your answer in the box. Round only your final answer-example-1

2 Answers

6 votes

Answer:

a = 15

Explanation:

The Law of Cosines

a^2 = 13^2 + 14^2 - 2(13)(14)Cos(67.4)

a^2 = 169 + 196 - (364 * 0.3843)

a^2 = 365 -140

a^2 = 225

a = 15

User Kiefer
by
5.7k points
4 votes

For this case, we have by definition the law of cosine states that:


a = \sqrt {b ^ 2 + c ^ 2-2 (b) (c) * cosine (67.4)}

We have to:


b = 13\\c = 14

Substituting:


a = \sqrt {13 ^ 2 + 14 ^ 2-2 (13) (14) * cosine (67.4)}\\a = \sqrt {169 + 196-364 * 0.38429532}\\a = \sqrt {365-139.8834965}\\a = \sqrt {225.1165035}\\a = 15.00388295

Rounding off we have:


a = 15

Answer:


a = 15