we have that
Marge says
7*0=7+0
7*0=0 ----> all numbers multiplied by zero is zero
and
7+0=7 ----> any number adds to zero is the same number
so
0=7 -----> is not true
therefore
Marge is not correct
Rules
Any number multiplied by zero is zero ------> multiplying by zero (Zero property of multiplication)
and
the Identity Law of Addition ----> Any number added to zero is equal to itself