Respuesta :

Answer:

ST = 100

Step-by-step explanation:

RS + ST = RT

(5x +2) + (7x -12) = 11x + 6

5x + 7x - 11x    = 6 - 2 + 12

                   x = 16

ST = 7x - 12 = 7*16 - 12 =  112 - 12

ST = 100