Understanding the Law of Sines and Cosines

When should you use the law of sines or cosines?

• When you have all sides known

• When dealing with right triangles

• When you have a non-right triangle

• When you have all angles known

In the first example, what is the missing side opposite the 40-degree angle?

• 8

• 5.2

• 7

• 6.5

How do you find the third angle in a triangle if you know the other two?

• Multiply the two angles

• Subtract the smaller angle from the larger one

• Divide the sum of the two angles by 2

• Add the two angles and subtract from 180

Why is it better to use original numbers rather than rounded values in calculations?

• To make calculations easier

• To simplify the process

• To avoid errors from rounding

• To save time

What is the first step in solving a triangle with side-angle-side information?

• Calculate the perimeter

• Find the largest angle

• Use the law of cosines

• Use the law of sines

In the second example, what is the calculated length of side B?

• 10.5

• 13.9

• 7

• 9

What is the next step after finding one side using the law of cosines?

• Calculate the area of the triangle

• Use the law of cosines again

• Find the perimeter

• Use the law of sines to find an angle

What is the sine inverse used for in triangle solving?

• To find a missing side

• To find a missing angle

• To calculate the area

• To determine the type of triangle

What is the final step in solving a triangle?

• Check if the triangle is right-angled

• Verify all sides are equal

• Calculate the area

• Ensure all angles add up to 180 degrees

What concept is introduced at the end of the video?

• The ambiguous case

• The Pythagorean theorem

• The concept of congruence

• The area of a triangle