Question 1208386:  Let A and B be sets. If elements of set A are also found in set B, then A is a subset of B.
 
 
The textbook writes it this way: A ⊆ B
 
 
Sample:
 
 
A = {x, x + 1, x + 2}
 
 
B = {a, b, c, x, x + 1, x + 2}
 
 
I see that the elements in set A are also in set B.
 
 
Conclusion: A ⊆ B
 
 
You say?  
 Answer by math_tutor2020(3817)      (Show Source): 
You can  put this solution on YOUR website!  
You are correct. Anything inside set A is also in set B. 
It might help to highlight the items you want to focus on. 
A = {x, x + 1, x + 2} 
B = {a, b, c, x, x + 1, x + 2}
 
 
This is what the Euler Diagram would look like 
  
circle A is entirely inside circle B. 
x,x+1,x+2 are in circle A. By extension they are also in circle B. 
a,b,c are in circle B, but outside circle A. 
 
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