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Question
`4x + 6/y = 15 and 6x - 8/y = 14.` Hence, find a if y = ax - 2.
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Solution
`4x + 6/y` = 15.........(1)
`6x - 8/y` = 14 ........(2)
Multiplying (1) by 4 and (2) by 3, we get,
`16x + (24)/y` = 60 ........(3)
`18x - (24)/y` = 42 ........(4)
Adding (3) and (4), we get,
34x = 102
⇒ x = `(102)/(34) = 3`
∴ `(6)/y`
= 15 - 4x
= 15 - 12
= 3
⇒ y = `(6)/(3) = 2`
Thus, the solution set is (3, 2).
Now,
y = ax - 2
⇒ 2 = 3a - 2
⇒ 3a - 4
⇒ a = `(4)/(3)`
= `1(1)/(3)`.
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