Question

Jawab plus caranya ya

Answer 1

1/S=1/f-1/s`
=1/10-1/30
=3-1/30
=2/30
s=30/2=15

Answer 2

S' = 30
f = 10
ditanya s =...?
1/s + 1/s' = 1/f
= 1/10 - 1/30
= 3/30 - 1/30
= 2/30
= 15