From trigonometry we know that:
if 
then,
(where
is an integer)
This can be rewritten in degrees as:
.............(Equation 1)
Now, in our case, 
Therefore, (Equation 1) can be written as:
..........(Equation 2)
Now, to find the correct options all that we have to do is replace n by relevant integers and find the values of
that match.
For n=2, (Equation 2) gives us:
.
Thus, 
Now, we know that: 
Let n=-1, then:

Thus, 
Likewise, 
Only the last option
will never match
because no integral value of
will ever give 
Thus the last option is the correct option.
Y = mx + b
slope(m) = -1
(7,2)...x = 7 and y = 2
now we sub and find b, the y int
2 = -1(7) + b
2 = -7 + b
2 + 7 = b
9 = b
so ur equation of this line is : y = -1x + 9.....can also be written as :
y = -x + 9....or if u need it in standard form, it is : x + y = 9
2x+3x+2=-4(cause y=3x+2)
5x=-6
x=-6/5
f(-6/5)=-8/5
negative 6 over 5
Equation - x = -3/10 + (10-1)
The original number is 9.3 because
x = -3/10 + (10-1)
x = -3/10 + 9
x = 9.3