Respuesta :

Answer:

30

Step-by-step explanation:

We know that in this case, since this is an intersection, the opposite sides are the same. Therefore, we can make a equation like this:

75 = 3x-15

Then we get:

90=3x

30=x

Answer:

The value of x is 30.

Step-by-step explanation:

The value of x is 30 because 3*30 equals 90 and 90 minus 15 is equal to 75. The total is equal to the angle ST.