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In △ABC, m∠C=95°, a=26, and b=17. Identify c rounded to the nearest tenth.

User Hutchbat
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1 Answer

8 votes

Answer:

32.3

Explanation:

According to the Law of Cosines, for any △ABC with sides lengths a, b, and c, a2=b2+c2−2bccosA; b2=a2+c2−2ac cosB; and c2=a2+b2−2abcosC.

Set up the equation for the Law of Cosines:

c2=a2+b2−2abcosC

Substitute the known values into the Law of Cosines:

c2=262+172−2(26)(17)cos 95°

Square the values and multiply:

с2=676+289−884cos95°

Add:

c2=965−884cos95°

Take the square root of both sides:

c=965−884cos95°

Calculate the value of cosine 95° on a calculator and solve for the positive value of square root to find c:

c≈32.3

Therefore, c≈32.3.

So, the length of side c is approximately 32.3 units.

User Alex Meyer
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