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Solve ABC subject to the given conditions if possible. Round the lengths of the sides and measures of the angles (in degrees) to one decimal place it necessary.

B=64 degrees, a=25, b=41

1 Answer

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To solve triangle ABC, we can use the Law of Cosines, which states that for any triangle with sides a, b, and c and opposite angles A, B, and C, respectively:

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

We are given B, a, and b, so we can solve for c as follows:

c^2 = 25^2 + 41^2 - 2(25)(41)cos(64)

c^2 = 625 + 1681 - 2135cos(64)

c^2 = 1829 - 2135*cos(64)

c^2 = 311.90

Taking the square root of both sides, we get:

c ≈ 17.7

So the length of side c is approximately 17.7 units.

To find the measures of angles A and C, we can use the Law of Sines, which states that for any triangle with sides a, b, and c and opposite angles A, B, and C, respectively:

a/sin(A) = b/sin(B) = c/sin(C)

We know a, b, and c, and we just solved for c, so we can use the Law of Sines to solve for angles A and C:

a/sin(A) = c/sin(C)

sin(A) = asin(C)/c

A = sin^{-1}(asin(C)/c)

A = sin^{-1}(25*sin(C)/17.7)

Similarly,

b/sin(B) = c/sin(C)

sin(B) = bsin(C)/c

B = sin^{-1}(bsin(C)/c)

B = sin^{-1}(41*sin(C)/17.7)

To find angle C, we can use the fact that the sum of the angles in a triangle is 180 degrees:

C = 180 - A - B

Using a calculator, we get:

A ≈ 41.6 degrees

B ≈ 74.1 degrees

C ≈ 64.3 degrees

Therefore, the measures of the angles in triangle ABC are approximately:

A ≈ 41.6 degrees

B = 64 degrees

C ≈ 64.3 degrees

And the lengths of the sides are approximately:

a = 25

b = 41

c ≈ 17.7

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