Q5 of 186 Page 4

Solve the following system of linear equations by cross - multiplication method.



[Hint: Let u = and v = ]

Given, pair of equations is


…(1)


…(2)


Let u and v


Now, the Eq. (1) and (2) reduces to


5u + 2v + 1 = 0


15u + 7v – 10 = 0


By cross - multiplication method, we have





On taking I and III ratio, we get




On taking II and III ratio, we get



⇒ v = 13


So, u …(a)


and v …(b)


On adding Eq. (a) and (b), we get






On putting the value of in Eq. (a), we get






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Which of the following pair of linear equations has unique solution, no solution or infinitely many solutions. In case there is a unique solution, find it by using cross - multiplication method:

x + y = 2


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Which of the following pair of linear equations has unique solution, no solution or infinitely many solutions. In case there is a unique solution, find it by using cross - multiplication method:

x + y = 2


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Solve the following system of linear equations by cross - multiplication method.

ax – ay = 2


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[Hint: Let u = and v = ]

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