Explanation:
For 1A
2y + 98° = 9y + 7° < being vertically opposite angles >
9y - 2y = 98° - 7°
7y = 91°
y = 13°
For 1B
9y + 7° = 9 * 13° + 7° = 124°
2y + 98° = 2 * 13° + 98° = 124°
The angles which are unknown are also vertically opposite angles so let unknown angles be x then
124° + 124 ° + x +x = 360° { being complete turn }
248° + 2x = 360°
2x = 112°
x = 56°
so all angles are 124° , 124° , 56°, 56°
For 2A
6y - 10 + 6y + 10 = 180° ( being linear pair)
12y = 180°
y= 15°
For 2B
6y - 10 = 6 * 15 - 10 = 80°
6y + 10 = 6 * 15 + 10 = 100°
Hope it will help :)