A=πr²
pool=π(y-4)²=π(y²-8y+16)
total=π(y+4)²=π(y²+8y+16)
walkway=total-pool
walkway=π(y²+8y+16)-π(y²-8y+16)=
π(y²+8y+16-y²+8y-16)=
π(16y)=
16πy
first option is answer
        
             
        
        
        
Answer: 
Step-by-step explanation:
 You have the equation  .
. 
 Then, to solve for the variable  from the equation you need:
 from the equation you need:
 Make the subtraction of the right side of the equation:
 (As the denominators are 1 and  , the least common denominator is
, the least common denominator is  )
)
 
 Multiply   to both sides:
 to both sides:
 
 Add  to both sides:
 to both sides:
 
 And finally divide both sides by  :
:
 
 
        
             
        
        
        
Answer:40 years 
Step-by-step explanation:
First you get 1% which is 9$ then you times it by 5 and get 45 multiply it by 20 you get 900 but since you want to double it then double the answer which is 40
 
        
             
        
        
        
Answer:
10 ft
Step-by-step explanation:
To get their total reach, we add the two numbers.
  5⅙
+4⅚
Add integers and fractions
  5⅙
<u>+4⅚
</u>
  9⁶/₆
Convert the fraction to an integer
⁶/₆ = 1
Add the 1 to the 9
9 + 1 = 10 ft
If Madison and Jade lay end to end, they will they reach 10 ft.
 
        
             
        
        
        
Answer:
 °
°
Step-by-step explanation:
"Theorem 9-13: The measure of an angle formed by two secants, two tangents, or a secant and a tangent drawn from a point outside the circle is equal to half the difference of the measures of the intercepted arcs."
Basically no matter what other circle, secant or tangent you get, you just use the formula  
If you need the outer angle, just put the other angles in and solve
If you need the far or near point angle, re-arrange the formula to get that value.