Respuesta :

Sum of angles of a triangle = 180°

91 + 10x - 4 + 8x +3 = 180
18x + 90 = 180
18x = 90
x = 5°
Sum of angles of a triangle = 180°

91 + 10x - 4 + 8x +3 = 180
18x + 90 = 180
18x = 90
x = 5°