Determinants 3 marks Questions, CBSE Class 12 PYQs 2024–2026

1 different 3 marks questions on Determinants from CBSE Class 12 Maths board exams 2024–2026, newest first.

Q273 marksShort AnswerDeterminants CBSE 2025 · 65/7/1

Let $2 x + 5 y - 1 = 0$ and $3 x + 2 y - 7 = 0$ represent the equations of two lines on which the ants are moving on the ground. Using matrix method, find a point common to the paths of the ants.

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Answer: (3, −1)

Write as $A X = B$ with $A = [2352]$ , $X = [x y]$ , $B = [17]$ .
$∣ A ∣ = 4 - 15 = - 11 \neq = 0$ , so $A^{- 1} = - \frac{1}{11} [2 - 3 - 5 2]$ .
$X = A^{- 1} B = - \frac{1}{11} [2 - 35 - 3 + 14] = - \frac{1}{11} [- 33 11] = [3 - 1]$ .
Common point is (3, −1).

Also asked in: 2025 65/7/2, 2025 65/7/3

Determinants: 3 marks Questions (CBSE Class 12)