Question

if 99x+101y=499 and 101x+99y=501 then x+y=​

Answer 1

99x + 101y= 499 .......1

101x + 99y = 501......2

By subtracting 1 and 2

101x + 99y = 501

-99x - 101y =-499

______________

2x - 2y = 2

2 (x-y) = 2

x-y =1_____3

By adding 1 &2

101x+99y=501

99x+101y=499

_________________

200x+200y = 1000

200(x+y)=1000

x+y = 5______4

By adding 3 and 4

x-y=1

x+y=5

_______

2x=6

x=3

x-y=1

3-y=1

-y= -2

y=2