Given : Each exterior angle is 135∘
Let each exterior angle be x.
Now, Each exterior angle+Each interior angle=180∘
∴ 135∘+x=180∘
x=180∘−135∘
=45∘
So, each exterior angle is 45∘
Also , each exterior angle =360∘n
45∘=360∘n
∴ n=360∘45∘
∴ n=8
So ,the number of sides is 8.