See the picture attached to better understand the problem
we know that
(x+20)+∠1=180°-------> by supplementary angles
∠1=160°-x
∠1+∠2=180°--------> by supplementary angles
∠2=180-(160-x)-----> ∠2=20+x
∠2=80°------> by corresponding angles
so
20+x=80
x=80-20-------> x=60°
the answer is
60°
we know that
(x+20)+∠1=180°-------> by supplementary angles
∠1=160°-x
∠1+∠2=180°--------> by supplementary angles
∠2=180-(160-x)-----> ∠2=20+x
∠2=80°------> by corresponding angles
so
20+x=80
x=80-20-------> x=60°
the answer is
60°