Answer :
They are not equivalent because 27-(63-8) is equal to -28 and (72-63)-8 is equal to 1.
For the first one is
27-(63-8)
27-55
28
The second one is (72-63)-8
9-8
1
They are not equivalent.
27-(63-8)
27-55
28
The second one is (72-63)-8
9-8
1
They are not equivalent.