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Question
For solving pair of equation, in this exercise use the method of elimination by equating coefficients :
13 + 2y = 9x
3y = 7x
Solution
13 + 2y = 9x ...(1)
3y = 7x ...(2)
Multiplying equation no. (1) by 3 and (2) by 2, we get,
39 + 6y = 27x ...(1)
+ 6y = 14x ...(2)
- - -
39 = 13x
x = 3
From (2)
3y = 7x
∴ 3y = 7(3)
∴ y = `21/3` = 7
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