Area of a circle: πr²
Data:
diameter:  21 cm
radius=diameter/2=21 cm/2=10.5 cm
area of this circle: π(10.5 cm)²=110.25π cm²  (≈346.36 cm²)
Answer: area=110.25π cm²
        
                    
             
        
        
        
Answer:
21°
Step-by-step explanation:
set it up
7x-1+3x-9=180
combine like terms
10x-10=180 
take the ten to the other side
10x=190
divide both sides by 10
x=19
plug x in
3(10)-9
30-9
21
(Incase you need it the other angle is 159°)
 
        
                    
             
        
        
        
Answer:
ans - all the snow would been removed ....bcause 4 *2.5 is 10
 
        
             
        
        
        
Answer:
x = 3.9
Step-by-step explanation:
So the whole angle PQS = 111 degrees 
it gave you part of it so subtract that off . 111 - 72 = 39 degrees 
10 times what equals about 39 degrees. 
39/ 10 = 3.9