Answer:
x = 10°
Step-by-step explanation:
99° + 3x + 12° + 39° = 180° {Being sum of angles of triangle }
150° + 3x = 180°
3x = 180° - 150°
3x = 30°
x = 30°/ 3
Hope it will help :)❤
in triangle
99+39+3x+12=180 sum of interior angle of the triangle is 180
3x=180-150
x=30/3=10
