Respuesta :

ceci03r

Answer:

39

Step-by-step explanation:

If i'm right, a triangle should add up to 180, so you add 39 and 102 to get 141. Then you subtract 141 from 180 and get 39

jcherry99

Answer:

39

Step-by-step explanation:

Remark

Every triangle has 180 degrees. The three angles must add to 180

Solution

x + 102 + 39 = 180

x + 141 = 180                     Subtract 141 from both sides.

x + 141-141 = 180-141

x = 39