Question

If 2x + y = 23 and 4x – y = 19, find the values of (5y – 2x) and `(y/x - 2)`.

Answer 1

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 equation (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.