Same chapter3 marksDifficulty: Medium
State the condition on the determinant of the coefficient matrix for a system of linear equations to have a unique solution.
Determinants
3 marksDifficulty: Medium
Find the area of the triangle with vertices (1, 2), (4, 6) and (−2, 3) using determinants.
Original Khojo Papers practice question — not from a past board paper.
Answer
7.5 square units
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
The area is half the modulus of the determinant of [[1, 2, 1], [4, 6, 1], [−2, 3, 1]], which expands to ½|1(6 − 3) + 4(3 − 2) + (−2)(2 − 6)| = ½|3 + 4 + 8| = ½ × 15 = 7.5 square units.
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