Uh, so, you're median is 81 already.
Since the middle two numbers are 82 and 80, you have to add them together and then divide by 2.
However, if you're trying to add a number in, adding 81 as it is would work as well.
Hope this helps!
Answer:
(5,-4) and (-5,6)
Step-by-step explanation:
Given:

Solve it. First, express y in terms of x from the second equation:

Substitute it into the first equation:

Apply zero product property:

So,

When
then 
When
then 
We get two solutions: (5,-4) and (-5,6)
There are only 2 perfect cubes in between 1000 and 2000.
11^3 = 1331
12^3 = 1728