1. How to find the area of a triangle when the altitude is not given ?

2. Area of Triangles Without Right Angles
Need: two sides and the included angle (SAS)

3. Area of Triangles Without Right Angles
Area= ab sin C
Or: Area = bc sin A
Or: Area = ca sin B
Note: They are really the same formula, just with the sides and angle changed.

4. Example:
b = 375m
c = 400m
A= 35°
Area= x 375 x 400 x sin35 =

5. Area of Triangles Without Right Angles
Heron's Formula
Need: three sides (SSS)

6. Heron's Formula

7. Example
S = = 38
Area = =

8. Practices:
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