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प्रश्न
Using determinants, find the area of ΔPQR with vertices P(3, 1), Q(9, 3) and R(5, 7). Also, find the equation of line PQ using determinants.
उत्तर
Given vertices of triangle ΔPQR are P(3, 1), Q(9, 3) and R(5, 7).
Area of ΔPQR = `1/2 |(3, 1, 1),(9, 3, 1),(5, 7, 1)|`
= `1/2 {3(3 - 7) - (9 - 5) + (63 - 15)}`
= `1/2 {-12 - 4 + 48}`
= `1/2 xx 32`
= 16 sq. units.
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