Use the law of sines to find the missing measurements when given two acute angles

The video tutorial explains how to solve for missing sides and angles in an oblique triangle using the Law of Sines. It begins by discussing the limitations of using the Pythagorean theorem and trigonometric identities in non-right triangles. The instructor then introduces the Law of Sines, explaining its application through proportions of side lengths and their corresponding angles. The tutorial includes step-by-step examples of solving for unknown sides using cross multiplication, emphasizing the importance of checking calculations for accuracy.

Why can't the Pythagorean theorem be used in the given triangle?

• The triangle is isosceles.

• The triangle has no angles.

• The triangle is equilateral.

• The triangle is not a right triangle.

What is the Law of Sines used for in this context?

• To calculate the perimeter of a triangle.

• To determine if a triangle is right-angled.

• To find missing angles and sides in an oblique triangle.

• To find the area of a triangle.

What is necessary to apply the Law of Sines?

• Knowing all angles.

• Having at least one complete ratio of side length to sine of its angle.

• Having a right angle.

• Knowing all side lengths.

What is the first step in finding side C using the Law of Sines?

• Guess the length of side C.

• Set up a proportion using the known side and angle.

• Use the Pythagorean theorem.

• Add all angles together.

What should you check on your calculator when using the Law of Sines?

• That it is in basic mode.

• That it is in scientific mode.

• That it is in radian mode.

• That it is in degree mode.

How is side A found using the Law of Sines?

• By using the sine of angle B.

• By using the sine of angle A and cross multiplication.

• By using the cosine of angle A.

• By using the tangent of angle A.

What is the final value of side A after calculation?

• 21.49

• 27.5

• 11.76

• 48