Step-by-step explanation:

Here in the given figure,

As the lines l and m are parallel to each other,

∴ (7x-20)° = (3x+20)° [∵Corresponding angles]

=> 7x-20 = 3x+20

=> 7x-3x = 20+20

=> 4x = 40

=> x = 40/4

= 10°

So, the value of x=10°

and the other two angles are,

(7x-20)° = (7×10-20)°

= (70-20)° = 50°

(3x+20)° = (2×10 +20)°

= (30+20)° = 50°