Question

please answer urgently...​

Answer 1

Answer:

Step-by-step explanation:

let (x,y) belong to both A x B and C x D ( A x B is a subset of C x D )

since x,y belongs to A x B

therefore x belongs to A and y belongs to B

similarly x belongs to C and y belongs to D

since x belongs to A and x belongs to C

A is a subset of C

similarly B is a subset of D