1 
theres 1 number for each number place
        
             
        
        
        
Answer:
3x-13 I believe
Step-by-step explanation:
You multiply the 3 to the x and the 5. This would equal 3x-15+2
You would then add the -15 and the 2. This would be the answer 3x-13
Sorry if it is wrong
 
        
             
        
        
        
X=-1 y=-1, x=1 y=5, x=3 y=11
        
                    
             
        
        
        
Answer:
1. a + b + c = 180
2. b + d = 180
3. d = a + c
Step-by-step explanation:
1. a + b + c = 180:
Angles in a triangle add up to 180
2. b + d = 180:
Angles in a straight line equal 180 because they are supplementary angles
3. d = a + c:
ΔACD is an exterior angle, and ΔACB is interior adjacent, hence ∠a and ∠c add up to ∠d