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Question
If 2x + y = 23 and 4x – y = 19, find the values of 5y – 2x and `y/x` – 2.
Solution
Given equations are
2x + y = 23 ......(i)
4x – y = 19 ......(ii)
On adding both equations, we get
6x = 42
So, x = 7
Put the value of x in equatuion (i), we get
2(7) + y = 23
14 + y = 23
y = 23 – 14
So, y = 9
Hence 5y – 2x
= 5(9) – 2(7)
= 45 – 14
= 31
`y/x - 2 = 4/x - 2`
= `9/7 - 2`
= `(9 - 14)/7`
= `-5/7`
Hence, the values of (5y – 2x) and `y/x` – 2 are 31 and `-5/7` respectively.
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