UPSEE Solved Model Paper 6

If a , b and c are in A. P. then 2b = a + c
or b =

a+c

2

Also the given line is ax + by + c = 0
Substituting the value of b we get
ax + (

a+c

2

)y + c = 0
i.e., 2ax + (a + c) y + 2c = 0
for all values of a and c the (1 , - 2) satisfy the equation
so the lines passes through a fixed point (1 , -2)