7 divided by 3 is 3.5
half of 6 is 3 and you can't evenly divided 7 by 2 so you would say that
3.5
+ 3.5
__________
7
Answer:
a) 150°
b) 30°
Step-by-step explanation:
It is easier to work the exterior angle first.
<h3>b)</h3>
The sum of exterior angles is 360°. The exterior angle at any vertex of a regular dodecagon will be 1/12 that:
360°/12 = 30° . . . the measure of one exterior angle
__
<h3>a)</h3>
The measure of an interior angle will be the supplement of the adjacent exterior angle.
180° -30° = 150° . . . the measure of one interior angle
You can find it by adding up the angles of the parallelogram.
Solution :
We have to prove that 
(De-Morgan's law)
Let 
then 
and 
and so 
and 
.
Thus, 
and so 
Hence, 
.........(1)
Now we will show that 
Let ⇒
Thus x is present neither in the set A nor in the set B, so by definition of the union of the sets, by definition of the complement.
and 
Therefore, 
and we have .............(2)
From (1) and (2),
Hence proved.
