Solving Missing Side Trig Ratio

Solving Missing Side Trig Ratio

By Scott Donnelly

Trig table is used to find the decimal value of sin cos or tan.

Trig Table

Open Ended

Look at the table, what do you notice about the values of sin, cos and tan?

Using Trig Table

Trig Value

Calculator

1. Make sure calculator is in Degree Mode

2. Make sure to use right trig ratio

3. Round at 4th decimal place.

Solving Missing Side

​Steps

1. Determine the trig ratio, you are going to use, by looking at angle and 2 sides. Use SOHCAHTOA

2. Set up equation with trig ratio and angle measurement.

3. Set trig and angle equal to ratio of sides.

4. Round angle decimal to 4th decimal place, using calculator or table

5. Solve for unknown.​

1. Determine the trig ratio, you are going to use, by looking at angle and 2 sides. Use SOHCAHTOA

2. Set up equation with trig ratio and angle measurement.

3. Set equal to ratio of sides.

4. Round angle decimal to 4th decimal place, using calculator or table

5. Solve for unknown.​

​

Solving Missing Side

​

Multiple Choice

Which 2 sides do you have comparing the angle?

• Opposite and hypotenuse

• Adjacent and hypotenuse

• Opposite and adjacent

Multiple Choice

Since we have opposite and adjacent which ratio will we use?

• Tan

• Sin

• Cos

Multiple Choice

How would we set up our equation

• $$\tan\ 63=\frac{x}{8}$$  

• $$\tan\ 63=\frac{8}{x}$$  

Solve the Problem

Multiple Choice

How would you set up this problem?

• $$\sin\ 36=\frac{8}{x}$$  

• $$\sin\ 36=\frac{x}{8}$$  

• $$\cos\ 36=\frac{x}{8}$$  

• $$\cos\ 36=\frac{8}{x}$$  

Multiple Choice

What will equation look like after you solve for $$\sin\ 36$$  

• $$.5878=\frac{x}{8}$$  

• $$.5878=\frac{8}{x}$$  

Math Response

What will x equal?

Type answer here

Correct Answer: 4.7

Deg^°

Rad

Math Response

Solve for x, round to nearest tenths. Use dry erase boards. Hint determine if you are using sin, cos or tan first.

Type answer here

Correct Answer: 4.9

Deg^°

Rad