Find the Missing Angle and Sides in a Right Triangle Using Trigonometric Functions

Find the length of the unknown side.

(Johnson, 2012)

What trig function can be used to solve for the missing angle?

• Sine

• Cosine

• Tangent

The correct ratio to solve for "x" is (a)  

• sin 28 = x/14

• cos 28 = x/14

• tan 28 = x/14

• tan 28 = 14/x

How do you solve for the missing variable in this triangle?

• Set up a sine ratio, then multiply to solve

• Set up a cosine ratio, then divide to solve.

• Set up a tangent ratio, then divide to solve

• Set up a sine ratio and then use the inverse sine to solve

When deciding on whether to use the Sine, Cosine or Tangent ratio, you must look at what is given and what is required to find on the triangle.

• True

• False

SOH CAH TOA can be used to find an angle or a side on a right-angled triangle.

• True

• False

A tourist views a deer from a height of 45 feet.  The horizontal distance between the tourist and the deer is 130 feet.  At what angle (x) should the tourist hold his camera to photograph the deer? Round your answer to the nearest degree.  

• 19 degrees

• 45 degrees

• 71 degrees

• 138 degrees 

Find the measure of angle A using an inverse trig ratio.

• 61.9 degrees

• 28.1 degrees

• 25.2 degrees

• .99997 degrees