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Solve the system of linear equations using the matrix method. 5x + 2y = 3 3x + 2y = 5

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प्रश्न

Solve the system of linear equations using the matrix method.

5x + 2y = 3

3x + 2y = 5

योग
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उत्तर

`[(5,2),(3,2)] [(x),(y)] = [(3),(5)]` AX = B

A = `[(5,2),(3,2)]`

X = `[(x),(y)]` or B = `[(3),(5)]`

Now, |A| = `|(5,2),(3,2)|`

= 10 − 6

= 4 ≠ 0

⇒ A−1 exists and hence the given equation has a minimal solution.

∴ Adj A = `[(2,-3),(-2,5)]^T = [(2,-2),(-3,5)]`

And A−1 = `1/|A|` (Adj A)

= `1/4 [(2,-2),(-3,5)]`

X = A−1B

⇒ `[(x),(y)] = 1/4 [(2,-2),(-3,5)] [(3),(5)]`

= `1/4 [(6-4), (-9 + 25)]`

= `1/4[(-4), (16)]`

= `[(-1),(4)]`

x = −1, y = 4

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अध्याय 4: Determinants - Exercise 4.6 [पृष्ठ १३६]

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एनसीईआरटी Mathematics Part 1 and 2 [English] Class 12
अध्याय 4 Determinants
Exercise 4.6 | Q 10 | पृष्ठ १३६

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