Answer:
See Explanation
Step-by-step explanation:
The question is incomplete, as there are no options to select from.
However, a general explanation is as follows.
Given

Required
Is
a correct expression?
Let


So:

becomes


Divide both sides by 2

Hence:
is incorrect
Answer:
-9
Step-by-step explanation:
The additive inverse of 4 is -4. Why? 4 + -4 = 0
-4 - 5 = -9
Answer:292820839382
Step-by-step explanation:
282739282992
I’d say 21 tbh unless the sum is half of the brothers age then it would be 9
Let the third side = x.
The sum of any two sides must be greater than the third side
14 + 9 > x
23 > x
14 + x > 9
x > -5
9 + x > 14
x > 5
So 5 < x < 23