Question

pls solve this numerical​

Answer 1

Which numerical 1,2,3

Answer 2

given
u=30 cm
f = -30cm
Using lens formula.
1/f = 1/v -1/u
on putting the values
1/-30=1/v -1/30
1/30+1/30=1/v
2/30=1/v
1/15=1/v
v=15cm
hence the distance of the image from the lens is 15cm