Question 1044054
Let x be an element in set C. Since x is in set C, it must be in BOTH set A and in set B because C is a subset of the intersection of A and B.


If you draw a venn diagram, the region where A and B overlap is where set C will be. Set C will either be the whole overlapping region or a smaller region inside this overlap. 


So this means that if x is in C, then x is in A. Also, x is in B. The element x is a general representative of any element in set C. So that means if C is a subset of A intersect B, then C is a subset of A and C is a subset of B