Which of the following is an equation$?$

Which of the following statements is incorrect$?$

In the systematic method of solving an equation, if we subtract a number from one side of the equation, then 

When a number added to LHS is transported, the addition operation

_____$+9\mathrm{x}=12\mathrm{x}$

_____$+ (-7\mathrm{y})=-11\mathrm{y}$

_____$+5\mathrm{p}=12\mathrm{p}$

_____$+(-4\mathrm{q})=14\mathrm{q}$