tolong di jawab! nomor 12 dan 13

12) x+25°+85°-5x= 90°
-4×+110°=90°
-4x = -20°
x= 5°
sudut AOB =85°-5x= 85°-5×5° = 85-25= 60°

13) 8x+30°+12x+10°=180°
20x+40°= 180°
20x =140°
x=7°

sudut LMN = 12x+10=12.7+10=84+10= 94°