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Examine the consistency of the system of equations. 2x − y = 5 x + y = 4 - Mathematics

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Question

Examine the consistency of the system of equations.

2x − y = 5

x + y = 4

Sum
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Solution

2x − y = 5

x + y = 4

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

⇒ AX = B

Now |A|

= `|(2,-1),(1,1)|`

= 2 + 1

= 3 ≠ 0

Hence, the system of equations is consistent.

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Chapter 4: Determinants - Exercise 4.6 [Page 136]

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 4 Determinants
Exercise 4.6 | Q 2 | Page 136

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