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Question
Solve the following pair of equations:
`x/3 + y/4 = 4, (5x)/6 - y/4 = 4`
Solution
Given pair of linear equations is
`x/3 + y/4` = 4
On multiplying both sides by LCM (3, 4) = 12, we get
4x + 3y = 48 ......(i)
And `(5x)/6 - y/8` = 4
On multiplying both sides by LCM (6, 8) = 24, we get
20x – 3y = 96 ......(ii)
Now, adding equations (i) and (ii), we get
24x = 144
⇒ x = 6
Now, put the value of x in equation (i), we get
4 × 6 + 3y = 48
⇒ 3y = 48 – 24
⇒ 3y = 24
⇒ y = 8
Hence, the required values of x and y are 6 and 8, respectively.
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