Sue solved an equation incorrectly, as shown below:

step 1: 7x = 28
step 2: x = 28 − 7
step 3: x = 21

which statement best explains why step 2 is incorrect in sue's solution?

she did not multiply 28 seven times.
she did not divide 28 by 7.
she did not multiply 28 by 7.
she did not add 7 to 28.