Respuesta :

tonb

Answer:

x=34

m∠S = 38

m∠T = 111

Step-by-step explanation:

Since the angles of a triangle should add up to 180, you can solve this equation:

31 + x+4 + 3x+9 = 180

the solution is x=34

Then the angles S and T can be found by substituting that value for x.

everimagining

Answer:

Step-by-step explanation:

In a triangle, there are 180 degrees.

180- 31 = 149 degrees

(x + 4) + (3x+9) = 149

x=34

X+ 4 = 38

3x +9 =111

X =34, T=111, S=38