9+12=m or 9+12=21
this is because when we start with m-9=12 we know that m is supposed to be the sum of 9 and 12.
if we check our work we will see this
9+12=21
9+12=21
m-9=12
21-9=12
 
        
             
        
        
        
Surface Area of a cone is 
<span>pi * r * s + pi * r^2 </span>
<span>s is the side length, since you have 10 ft diameter, you know radius is 5. And since height is 12. With this, you have a 5-12-13 triangle, and s=13. </span>
<span>so </span>
<span>pi * 5 * 14 + pi * 5^2 = 95 pi or 298.3 </span>
<span>divide 298.3 by 15 and you get 19.88, you round up, so 20 is the answer </span>
        
             
        
        
        
Answer:
J =2m -3
Step-by-step explanation:
2m is twice Monica's age 
-3 represents 3 years younger 
 
        
             
        
        
        
Answer:   
24m-28
Step-by-step explanation:
(6m-7)x4
24m-28