Calculating Missing Angles and Side Lengths in Non-Right Angle Triangles

The video tutorial explains how to find missing angles and side lengths in non-right angle triangles using the sine and cosine rules. It covers when to use each rule, provides examples, and demonstrates the process of solving for missing values. The sine rule is used when an angle and its opposite side are known, while the cosine rule is applied when two sides and the included angle or all three sides are known. The tutorial emphasizes the importance of understanding and rearranging formulas to find missing values.

When should you use the sine rule in a non-right angle triangle?

• When you have two angles and a side

• When you have all three sides

• When you have two sides and the included angle

• When you have an angle and its opposite side

What is the correct form of the sine rule to find a missing angle?

• Length over angle

• Angle over length

• Angle times length

• Length plus angle

In the given example, what is the known angle used in the sine rule?

• 125 degrees

• 35 degrees

• 68 degrees

• 90 degrees

What is the cosine rule formula for finding a missing length?

• a^2 = b^2 - c^2 + 2bc cos A

• a^2 = b^2 - c^2 - 2bc cos A

• a^2 = b^2 + c^2 - 2bc cos A

• a^2 = b^2 + c^2 + 2bc cos A

When using the cosine rule, what information must you have?

• All three angles

• Two sides and the included angle, or all three sides

• Two angles and a side

• One side and one angle