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Question
Solve the following simultaneous equation.
`x/3 + 5y = 13 ; 2x + y/2 = 19`
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Solution
`x/3 + 5y = 13` ...(I)
x + 15y = 13 × 3
∴ x + 15y = 39 ...(II)
`2x + y/2 = 19` ...(III)
`(4x+y)/2 = 19`
4x + y = 19 × 2
∴ 4x + y = 38 ...(IV)
Multiplying (II) with 4 we get,
4x + 60y = 156 ...(V)
Subtracting (IV) from (V),
4x + 60y = 156
4x + y = 38
- - -
59y = 118
⇒ y = 2
Putting the value of y in (IV) we get,
∴ 4x + y = 38
⇒ 4x + 2 = 38
⇒ 4x = 36
⇒ x = 9
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∴ 10x + y + 10y + x = `square`
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∴ x – y = 2 ......(ii)
Solving equations (i) and (ii)
∴ x = `square`, y = `square`
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