Question

4/x +3/y=1 8/x-9/y=7​

Answer 1

4/x + 3/y = 1

8/x - 9/y = 7

Let, 1/x = a

and 1/y = b

Now,

4a + 3b = 1     ----- multiply by (9)

8a - 9b = 7    --------- multiply by(3)

why multiplied?

because we have to make coefficients of any one variable equal..

36a + 27b = 9   --------------- eq1

24a - 27b = 21   ----------------- eq2

------------------------

60a         = 30

a = 30/60

a = 1/2

put the value pf 'a' in any one of equation to get value of 'b'

36a + 27b = 9

36(1/2) + 27b = 9

18 + 27b = 9

27b = 9 - 18

27b = -9

b = -9/18

b = -1/2

Now,

a = 1/x                                       b = 1/y

1/2 = 1/x                                    -1/2 = 1/y

x = 2                                           y = -2