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प्रश्न
For solving pair of equation, in this exercise use the method of elimination by equating coefficients :
3x - y = 23
`x/3 + y/4 = 4`
उत्तर
3x - y = 23 ...(1)
`x/3 + y/4 = 4`
4x + 3y = 48 ...(2)
Multiplying equation no. (1) by 3
9x - 3y = 69 ....(3)
Adding equation (3) and (2)
9x - 3y = 69
+ 4x + 3y = 48
13x = 117
x = 9
From (1)
3(9) - y = 23
∴ 27 - y = 23
∴ y = 27 - 23
∴ y = 4
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संबंधित प्रश्न
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