Proof

[blazing sinew]

proof:
let x be an element of A, and y an element of B
then the ordered pair (x,y) is an element of A x B
using our assumption we can deduce that x is an element of C, and y is an element of D
therefore (x,y) is also an element of C x D
thus proving the conclusion

[next river]

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[blazing sinew]

is my proof correct ?

[abstract aspen]

yes!

[blazing sinew]

okay good

[blazing sinew]

+close