Answer:
Base 1 plus Base 2 divided by 2 times height
Step-by-step explanation:
The base 1 is 5 and base 2 is 7 and height is 3.5
Since there is a 180 degrees in a straight line and we know that the intersection of one angle is 27 degrees we can can say 180 -27 = 153 degrees. So the four angles would be 27, 27 153, 153