Answer:
See Below. 
Step-by-step explanation:
We are given that ∠A = ∠D, and we want to prove that ΔACB ~ ΔDCE. 
Statements:                                    Reasons: 
 
                                    
 
                        
 
                        
 
        
                    
             
        
        
        
The answer is 9
You divide by 1215 by 15 and the answer is 81
Then you find the square root of 81 and the answer is 9
        
                    
             
        
        
        
3(x-3)-15 = 0
3(x-3) = 15
3x-9 = 15
3x = 24
x = 8
        
                    
             
        
        
        
1) 1, -2..for the first question
        
             
        
        
        
Answer:
2,3,6,7
Step-by-step explanation: Standard form is Ax+By=C
Number one and 4 are in point slope form. Number 5 has no y.