13.4A Area Law of Sines

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Algebra 2 13.4A Area of Triangle, Law of Sines Obj: able to find exact values of trigonometric functions for general angles; able to use reference triangles Area of a Triangle B The area of any triangle is given by one half the product of the lengths of two sides times the sine of their included angle. 1 c Area = bc sin A a 2 1 Area = ab sin C 2 A 1 b C Area = ac sin B 2 Find the area of the triangle . 1. B 3 C 25 ° 6 A Oblique triangles are triangles that have no right angles . C Use Law of Sines to solve (AAS or ASA) a b Law of Sines If ABC is a triangle with sides a, b, and c, a b c sin A SinB SinC then = = or = = sin A sin B sin C a b c A c B 2. Given a triangle with A = °,70 B = 80 a , a = 30 in ., find the remaining side and angles. Round sides to the nearest tenth and angles to the nearest degree. There has to be an angle and a side across from each other to use the Law of Sines. So fill in the table below. A = a = B = b = C = c = 3. Given a triangle with B = 56 a ,C = 84 a ,b = 15 feet , find the remaining angle and sides. Round sides to the nearest tenth and angles to the nearest degree. There has to be an angle and a side across from each other to use the Law of Sines. So fill in the table below. A = a = B = b = C = c = 4. Given a triangle with A = °,35 c = 10 m, B = 85 a , find the remaining side and angles. Round sides to the nearest tenth and angles to the nearest degree. There has to be an angle and a side across from each other to use the Law of Sines. So fill in the table below. A = a = B = b = C = c = Rate yourself on how well you understood this lesson. I understand I don’t get I sort of I understand most of it but I I got it! it at all get it it pretty well need more practice 1 2 3 4 5 What do you still need to work on? .

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