To check whether a function is odd or even, we simply substitute the argument by its negative version, namely "x" by "-x".
if the expression simplifies to resemble the original expression, that simply means the expression is
even. If it resembles the original negative expression, is
odd.

well, that doesn't look like the original
- 2x³ - 9, so is not
even.
and -f(x) would be
2x³ + 9, and that doesn't look like either, so is not
odd.
thus is neither.
2. Angle Addition Postulate as they are adding both angles
3. 60 + 40 = m <ABC because it's a substitution
4. 100 = m <ABC as it is simplified already
5. Definition of obtuse angle
Answer:
Step-by-step explanation:
P = 5x
P = 5(3) = 15
4-7x= 39
Subtract 4 from both sides
-7x= 35
Divide both sides by -7
x= -5
The value of x+1= (-5)+1= -4.