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The radius of the circumscribed circle of the triangle ABC is 15 cm. Given that B is a 49° angle, find the length of side AC.

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Based on the given information, the length of side AC in triangle ABC is approximately 22.641 cm.

How to calculate the required length

In a triangle, the circumradius (R) is related to the side lengths by the formula:

R = (abc) / (4A)

Where a, b, and c are the side lengths of the triangle, and A is the area of the triangle.

In triangle ABC, the given angle B is 49°.

Use the Law of Sines to find the length of side AC.

According to law of Sines:

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

Given that B is 49°, set up the equation as follows:

sin(A) / AC = sin(49°) / BC

Since the circumradius (R) is given as 15 cm

AC = 2R * sin(A)

Substitute this into the equation above

sin(A) / (2R * sin(A)) = sin(49°) / BC

1 / (2R) = sin(49°) / BC

Now, substitute the value of R (15 cm) and solve for BC:

1 / (2 * 15) = sin(49°) / BC

BC = sin(49°) * (2 * 15)

Using a calculator to evaluate sin(49°) ≈ 0.7547

BC ≈ 0.7547 * (2 * 15)

BC ≈ 0.7547 * 30

BC ≈ 22.641 cm

Therefore, the length of side AC in triangle ABC is approximately 22.641 cm.

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