Answer:
the last choice
Step-by-step explanation:
two functions are said to be inverse when they are symmetric about the line y=x
 
        
             
        
        
        
Answer:
Total laps = 10d
Step-by-step explanation:
Let c = Carl's laps
d = Daria's laps
e = Erin's laps
c = 3d
c = e/2
c + d + e = totals laps
We can insert 3d in place of c in the third equation
3d + d + e = total laps
Also, e/2 equals 3d
e/2 = 3d
Multiply both sides by 2
(e/2 = 3d)2
e = 6d
Insert the new e
3d + d + 6d = 10d = totals laps
 
        
             
        
        
        
Answer:
16.2 m
Step-by-step explanation:
First, we can draw a picture. The cable goes from the top of the pole to the ground (with the pole on the right in my drawing), and the point on the ground is 10 m away from the base of the pole. This forms a right triangle, with the right angle being between the 10 m distance and the pole itself. We can then apply the Pythagorean Theorem, so 
a²+b²=c², with c being the side opposite the right angle (the cable), getting us
10²+(length of pole)² = 19²
19²-10²=(length of pole)²
= 261
square root both sides to isolate the length of the pole
length of pole ≈ 16.2 m