Answer:
a = 12, <ONS = 68 , <OAB = 68
Step-by-step explanation:
Since they are in a parallelogram that means that some of these angles equal each other or are the same.
<ONS = <OAB
(4a + 20)° = (80 - a)°
5a = 60
a = 12
Plug an into the to get angles.
<ONS = 4a+20
<ONS = 4*12+20
<ONS = 48+20
<ONS = 68
<OAB= 80-a
<OAB = 80-12
<OAB = 68
