Complete question
A 29-meter ladder is sliding down a vertical wall so the distance between the top of the ladder and the ground is decreasing at 7 meters per minute. At a certain instant, the bottom of the ladder is 21 meters from the wall.
What is the rate of change of the distance between the bottom of the ladder and the wall at that instant(in meters per minute)
Answer:

Step-by-step explanation:
From the question we are told that
Slant height 
Change in Vertical height 
Horizontal length 
Generally in finding the distance form the top to the bottom of the wall it is mathematically given by




Generally solving for the differential equation is mathematically represented as







Answer:
Forgive me if I'm wrong, but if I am correct that would be 30 people.
Abc would be the same order with Def so the coordinate to f is C
In order to know the answer for this one, let us analyze the whole problem.
Given that the store already lose $100 stolen by the guy, this guy also bought a merchandise worth 70$, and gets a change of $30. The merchandise was paid, but still, the store lost $100, and then an additional $30, for giving it back to the guy. So the total lost of the store would be $130. Hope this answer helps.
4x-2x=-10+2
2x=-8
x=-8/2
x=-4