I only (sort of) know 3 and 4
3. Andle 1 is an example of an angle bigger than

I don't know what you call it.
4. If you have a straight line, both angles (or more) added up need to be

so if angle 1 is 129, 180-129=51
angle 2 is

If 1 is what is the relationship between the two angles, then maybe the answer is that they both added up need to be 180 degress (?)
And 2 is probably the same as 3 but with angle 2, angle two is an example of an angle smaller than 90 degrees
Always true because addition and subtraction is commutative
-6.2-(-3.96) = -2.24
-3.96-(-6.2)= -2.24
5.71+2.84=8.55
2.84+5.71=8.55
Hope this helped :)
The quotient of a number and three can be written as n/3
We can set up a system of equations:
x + y = 12
x - y = 4
Adding these two together:
2x = 16
x = 8
Substituting 8 in the first equation:
8 + y = 12
y = 4
Hope this helps!
You might want to see what other people say but I think that it is 40