Mr. Mole's burrow was at an altitude of 6 meters below the ground.
Step-by-step explanation:
Step 1:
We need to determine the distance that Mr. Mole covers in a single minute.
To do that we divide the difference in values of altitude by the difference in the time periods.
For the first case, Mr. Mole had traveled -18 meters in 5 minutes.
We also have, he traveled -25.2 meters in 8 minutes.
Step 2:
The distance he covered in 1 minute 

So with every minute, Mr. Mole digs down an additional 2.4 meters below the surface.
To determine where Mr. Mole's burrow is we subtract the distance traveled in 5 minutes from -18.
The altitude of Mr. Mole's burrow 
So Mr. Mole's burrow was at an altitude of 6 meters below the ground i.e. -6 meters.
A and B Definitely. 3 and 17, -3 and -17
Hello!
Here are the steps to your problem:
3x + 5 = x - 3
3x -x = -3 -5
2x = -8
x = -4
I hope this helps you! Have a lovely day!
-Mal
Answer:
There are 12 pentapods and 8 Tripods, which in total add up to 84 feet.
Step-by-step explanation:
Given that both the Tripods and the Pentapods have, at least, 3 feet (the Pentapods have 5), and that in total between both groups they add 20 heads and 84 feet, the following logical reasoning can be made:
If there are 20 heads, there are 20 Martians in all. Each of them has, at least, 3 feet, with which in principle the 20 Martians would add up to a total of 60 feet (20 x 3). Therefore, there is a surplus of 24 feet (84 - 60).
If the Pentapods have 2 feet more than the Tripods, the number of Pentapods in the total Martians is determined by that difference. Thus, if there are 24 feet left, there are 12 Pentapods (24/2).
Therefore, in the group of Martians there are 12 pentapods (12 x 5 = 60) and 8 Tripods (8 x 3 = 24), which in total add up to 84 feet (60 + 24).