If the shape of the room is a square, then the square root of the sum of the squares of the the two adjacent sides will give the diagonal.
i.e.

Since the square root of the sum of the squares of the the two adjacent sides is 24.04 and not 18.79, therefore, the shape of the room is not a square.
 
        
        
        
Answer: 2m + 2m
Step-by-step explanation: m + m is 2m and the same for the other two m's which is why m + m + m + m is 2m + 2m
 
        
                    
             
        
        
        
The truck in this example is 14 feet tall if it's shadow is 12 feet long.
        
             
        
        
        
Answer:
-2 & 8
Step-by-step explanation:
   x + y = 6
+(x - y = -10)
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   2x    = -4
x = -2
-2 + y = 6
y = 8