<PRE><B>Question 1107197</B>
Four of the interior angle of a pentagon are 80-y°, 80+y°,120-y°,120+y°. The size of the 5th interior angle must be??? 
-----
The sum of the interior angles of a pentagon are (5-1)*180 = 720 degrees
==============
Equation::
80-y + 80+y + 120-y + 120+y + 5th = 720
200+200 + 5th = 720
5th = 320 degrees
-------------
Cheers,
Stan H.
----------</PRE>