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Find the Area of the Triangle with Vertice at the Point: (3, 8), (−4, 2) and (5, −1) - Mathematics

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प्रश्न

Find the area of the triangle with vertice at the point:

(3, 8), (−4, 2) and (5, −1)

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उत्तर

\[∆ = \frac{1}{2}\begin{vmatrix}3 & 8 & 1 \\ - 4 & 2 & 1 \\ 5 & - 1 & 1\end{vmatrix} \] 

\[ ∆ = \frac{1}{2}\begin{vmatrix}3 & 8 & 1 \\ - 7 & - 6 & 0 \\ 5 & - 1 & 1\end{vmatrix} \left[\text{ Applying }R_2 \to R_2 - R_1 \right]\] 

\[ ∆ = \frac{1}{2}\begin{vmatrix}3 & 8 & 1 \\ - 7 & - 6 & 0 \\ 2 & - 9 & 0\end{vmatrix} \left[\text{ Applying }R_3 \to R_3 - R_1 \right]\] 

\[ ∆ = \frac{1}{2}\begin{vmatrix}- 7 & - 6 \\ 2 & - 9\end{vmatrix}\] 

\[ ∆ = \frac{1}{2}\left( 63 + 12 \right)\] 

\[ ∆ = \frac{1}{2}\left( 75 \right) = \frac{75}{2}\text{square units }\]

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पाठ 6: Determinants - Exercise 6.3 [पृष्ठ ७१]

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आरडी शर्मा Mathematics [English] Class 12
पाठ 6 Determinants
Exercise 6.3 | Q 1.1 | पृष्ठ ७१

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