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प्रश्न
Solve the following systems of equations:
`x/7 + y/3 = 5`
`x/2 - y/9 = 6`
उत्तर
The given system of equation is
`x/7 + y/3 = 5` ...(i)
`x/2 - y/9 = 6`.....(ii)
From (i), we get
`=> (3x + 7y)/21 = 5`
`=> 3x + 7x = 105`
`=> 3x = 1.5 - 7y`
`=> x = (105 - 7y)/3`
From (ii), we get
`(9x - 2y)/18 = 6`
=> 9x - 2y = 108......(iii)'
Substituting x = `(105 - 7y)/3` in (iii) we get
`9(105 - 7y)/3 - 2u = 108`
`=> (948 - 63y)/3 - 2y = 108`
=> 945 - 63y - 6y = 108 x 3
=> 945 - 69y = 324
`=> 945 - 324 = 69y`
=> 69y = 621
=> y = 621/69 = 9
Putting y = 9in x = `(1105 - 7y)/3` we get
`x = (105 - 7 xx 9)/3 = (105 - 63)/3`
`= x = 42/3 = 14`
Hence, the solution of thee given system of equations is x = 14, y = 9
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