Try this:
1. sum of numbers is x+y=67, the difference between them is x-y=11
2. it is possible to make up and resolve the system:
 
 
        
        
        
Answer:
710
Step-by-step explanation:
81+74+72+66+67+72+66+66+72+65+71= 701
701 rounded to the nearest tenth is 710
 
        
             
        
        
        
The given equation with t -1 is:
(t – 1)^3 + 6 (t – 1)^2 + 12 (t – 1) + 8
Expand each term before combining for easier visualization:
(t – 1)^3 = t^3 – 3 t^2 + 3t – 1
6 (t – 1)^2 = 6 t^2 – 12 t + 6
12 (t – 1) = 12 t - 12
Then substitute and combine:
-> t^3 – 3 t^2 + 3t – 1 + 6 t^2 – 12 t + 6 + 12 t – 12 + 8
t^3 + 3 t^2 + 3 t + 1	(ANSWER)
        
             
        
        
        
Step-by-step explanation:
-1,6 is -1 left 6 up
1,-6 is 1 right -6 down
6,-1 is 6 right -1 down
 
        
             
        
        
        
The vertex form is y=(x-4)^2-1