Respuesta :

Answer:

[tex]x=14[/tex]

Step-by-step explanation:

The angles of a triangle add to 180, add the angles and solve for x

Answer:

x = 14

Step-by-step explanation:

3x + 9 + 5x - 1 + 4x + 4 = 180 because triangles have 180 degrees

12x + 12 = 180

180 - 12 = 168

12x = 168

168/12 = 14

x = 14