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Question
Solve the following simultaneous equation.
`x/3 + y/4 = 4; x/2 - y/4 = 1`
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Solution
`x/3 + y/4 = 4` ...(I)
`x/2 - y/4 = 1` ...(II)
Multiplying (I) with LCM of 3 and 4 which is 12, we get,
4x + 3y = 48 ...(III)
Multiplying (II) with LCM of 2 and 4 which is 4, we get,
2x - y = 4 ...(IV)
Multiplying (IV) with 2,
4x - 2y = 8 ...(V)
Subtracting (V) from (III)
4x + 3y = 48
4x - 2y = 8
- + -
5y = 40
⇒ y = 8
Putting this value of y in (IV) we get,
∴ 2x - y = 4
⇒ 2x - 8 = 4
⇒ 2x = 12
⇒ x = 6.
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