Step-by-step explanation:
For no. 11
13x + 15 = 19x - 9 ( being opposite sides of parallelogram)
19x - 13x = 15 + 9
6x = 24
x = 4
Also,
4y + 7 ° + 10y - 37° = 180° { being co-interior angles }
14y - 30° = 180°
14y = 210°
y = 210° / 14
y = 15°
For no. 12
5x + 38° = 8x - 19° { being opposite angles of parallelogram }
8x - 5x = 38° + 19°
3x = 57°
x = 19°
Hope it will help :)
