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

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MCQ
Fill in the Blanks

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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2022-2023 (March) Sample

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