# Geo.4 Right Triangle Trigonometry

### Lesson 1

• I can explain why knowing one acute angle in a right triangle determines the ratio of the side lengths.

### Lesson 2

• I can determine the side lengths of triangles with 45, 45, and 90 degree angles.

### Lesson 3

• I can determine the side lengths of triangles with 30, 60, and 90 degree angles.

### Lesson 4

• I can build a table of ratios of side lengths of right triangles.

### Lesson 5

• I can use a table of ratios of side lengths of right triangles to estimate unknown angle measures.
• I can use a table of ratios of side lengths of right triangles to estimate unknown side lengths.

### Lesson 6

• I can use cosine, sine, and tangent to find side lengths of right triangles.

### Lesson 7

• I can use cosine, sine, and tangent to find the height of an object.

### Lesson 8

• I can explain why $\sin(\theta)=\cos(90-\theta)$.

### Lesson 9

• I can use arccosine, arcsine, and arctangent to find angle measures in right triangles.

### Lesson 10

• I can use trigonometry to solve problems.

### Lesson 11

• I can explain how to use regular polygons to approximate the value of $\pi$.