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The Area of a Triangle: SAS Formula

The Side Angle Side Formula

The Side Angle Side formula for finding the area of a triangle is a way to use the sine trigonometric function to calculate the height of a triangle and use that value to find the area of the triangle.
The formula $$ =\frac{1}{2} \cdot c \cdot b \cdot sin(\text{A}) $$
or, in general
$$ Area = \frac{1}{2} \cdot side_1 \cdot side_2 \cdot sin(\text{included angle}) $$
Visit this url, if you want to review what is meant by 'included angle'.

Where does this formula come from

question
Can you identify which triangle below has an included angle?
Answer
identify included angle

Example 1
Side angle side area example 1
Step 1) Identify two sides and the included angle!
Do Step 1
Step 2) Apply the formula!
Do Step 2


Practice Problems


Side angle side area example 1
Step 1) Identify two sides and the included angle!
Step 1
Step 2


Side angle side area example 1
Step 1) Identify two sides and the included angle!
Step 1
Step 2


Side angle side area example 1
Step 1) Identify two sides and the included angle!
Step 1
Step 2
Choose Angle
All Side Lengths?
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