Answer:
Y= 42
Step-by-step explanation:
The answer would be 42 because if x=9 and the equation is 5x you have to multiply and that will give you 45 and then subtract 3 which would give you  42
 
        
                    
             
        
        
        
Yes it’s a rectangle because the diagonals bisect each other, and they are equal in length.
        
                    
             
        
        
        
172.9
You find it by multiplying each side of the triangle by the height (9) and adding the results together.
A(lateral) = 8 * 9.1 + 3 * 9.1 + 8 * 9.1
= 72.8 + 27.3 + 72.8
= 172.9