Answer:
a+3
Step-by-step explanation:
You cannot go any further in answering this question.  These two terms are not like terms so they cannot be combined.  Therefore, the answer is just a+3 itself.
 
        
             
        
        
        
A square, rectangle, rhombus (I think)
        
                    
             
        
        
        
Answer:
Step-by-step explanation:
+55+%2B+.5x+=+.7x+
+.2x+=+55+
+x+=+275+
 
        
             
        
        
        
Involving the second and no higher power of an unknown quantity or variable.
        
                    
             
        
        
        
Any answer less than one would work, soothe answers are A and D