How to use the cosine function to find the missing side of a triangle

The video tutorial explains how to identify the adjacent side in a right triangle when given the hypotenuse. It demonstrates using the cosine function to solve for the unknown side length, X, by setting up the equation cosine of 32 degrees equals X over 5. The tutorial guides students through solving the equation by multiplying both sides by 5 and using a calculator to find the approximate value of X, rounded to the third decimal place.

What is the relationship between the given side and the angle in this problem?

• Opposite side

• Adjacent side

• None of the above

• Hypotenuse

Which trigonometric function is used when you have the adjacent side and the hypotenuse?

• Secant

• Cosine

• Tangent

• Sine

If the cosine of 32 degrees equals X/5, what is the value of X?

• 5 * sin(32 degrees)

• 5 * tan(32 degrees)

• 5 * cos(32 degrees)

• 5 / cos(32 degrees)

What should you ensure about your calculator before performing the calculation?

• It is in standard mode

• It is in radians mode

• It is in degrees mode

• It is in scientific mode

To what decimal place should you round your answer in this class?

• Second decimal place

• Third decimal place

• First decimal place

• Fourth decimal place