Answer :

Answer:

D) 80°

Step-by-step explanation:

(n - 2)180 = 4(180) = 720

78 + 134 + 136 + 132 + 2x + x = 720

3x + 480 = 720

3x = 240

x = 80

Answer:

The answer is D:80 degrees.

Step-by-step explanation:

Other Questions