Answer:
4d (the variable is usually x, though).
Step-by-step explanation:
Because 4 x the amount of fish in each tank = total amount of fish
 
        
             
        
        
        
C = -840
Isolate C by subtracting 900 on both sides:
C = 60-900
Which then gives u C = -840
        
                    
             
        
        
        
Pyramid Surface Area = (½ * Perimeter of Base * Slant Height) + Base Area
Base perimeter = 4 * 18 = 72 inches
Base Area = 18*18 = 324 square inches
Pyramid Surface Area = (.5 * 72 * 12) + 324
Pyramid Surface Area = 432 + 324
Pyramid Surface Area = 756 square inches
Source:
http://www.1728.org/volpyrmd.htm
 
        
             
        
        
        
Answer: -2
Step-by-step explanation: