Answer:
Pi also appears in the calculations to determine the area of an ellipse and in finding the radius, surface area, and volume of a sphere.  
Step-by-step explanation:
The number represented by pi (π) is used in calculations whenever something round (or nearly so) is involved, such as for circles, spheres, cylinders, cones, and ellipses. Its value is necessary to compute many important quantities about these shapes, such as understanding the relationship between a circle’s radius and its circumference and area (circumference=2πr; area=πr²).
Our world contains many round and near-round objects; finding the exact value of pi helps us build, manufacture, and work with them more accurately.
 
        
                    
             
        
        
        
8X - 6X = -18
2X = -18
X = -9.
Hope this helps!
        
                    
             
        
        
        
Answer:
1.)4188.79
2.) 7238.23
3.)1.02
4.)4189
5.)170 cm³
Step-by-step explanation:
1.) 4πr2 * 5
2.) 4πr2 * 12
3.) V = 4/3(PI*r3). *4.5
4.) V = 4/3 π r ^3 * 10
5.) Given:
Cylindrical container: height = 18 cm ; diameter = 6 cm.
3 balls each have a radius of 3 cm.
Volume of a cylinder = π r² h
V = 3.14 * (3cm)² * 18 cm
V = 508.68 cm³
Volume of rubber ball = 4/3  π r³
V = 4/3 * 3.14 * (3cm)³
V = 113.04 cm³
113.04 cm³  * 3 balls = 339.12 cm³
508.68 cm³ - 339.12 cm³ = 169.56 cm³ or 170 cm³
There is 170 cm³ free space in the container.
 
        
             
        
        
        
Answer:
points (2,3) and (-2,9)
Step-by-step explanation:
 
        
             
        
        
        
Treat 

 as the boundary of the region 

, where 

 is the part of the surface 

 bounded by 

. We write

with 

.
By Stoke's theorem, the line integral is equivalent to the surface integral over 

 of the curl of 

. We have

so the line integral is equivalent to


where 

 is a vector-valued function that parameterizes 

. In this case, we can take

with 

 and 

. Then

and the integral becomes


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