Respuesta :

dudemandomaille

Answer:

x= 43

measure= 142'

Step-by-step explanation:

We know that a triangle has a sum of 190 degrees we have 17' and 21'

add them together = 38

180-38= 142' (2nd part of answer)

3x + 10 = 142

3x= 132

x= 43 (1st part of answer)