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The area of a triangle with vertices A, B, C is given by ______.

#### Options

`|vec("AB") xx vec("AC")|`

`1/2|vec("AB") xx vec("AC")|`

`1/4|vec("AC") xx vec("AB")|`

`1/8|vec("AC") xx vec("AB")|`

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#### Solution

The area of a triangle with vertices A, B, C is given by `underline(bb(1/2|vec(AB) xx vec(AC)|))`.

**Explanation:**

The area of the parallelogram with adjacent sides AB and AC = `|vec("AB") xx vec("AC")|`. Hence, the area of the triangle with vertices A, B, C = `1/2|vec("AB") xx vec("AC")|`

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