# Area of triangles:$\frac{1}{2} ab$ sinC - Trigonometric Ratios and Angle Measures

### Area of triangles:$\frac{1}{2} ab$ sinC

#### Lessons

###### Notes:

###### In this lesson, we will learn:
- Proof: Area of Triangle =$\frac{1}{2}ab \sin C$
- Finding the Area of a Triangle Given 2 Sides and the Angle in Between
- Area of Isosceles Triangles
- Area of Equilateral Triangles
- Determining the Areas of Different Triangles

__Notes:__

- The base and height of a triangle must be perpendicular to each other.
- The traditional formula for the area of a triangle = $\frac{1}{2} \times base \times height$
- An isosceles triangle has two sides of equal length.
- An equilateral triangle has three sides of equal length and all the inner angles equal to 60°.
- Angles inside a triangle add up to 180°.
- Pythagorean Theorem: $a^{2}+b^{2}=c^{2}$

__Notes:__