Question

Add the following

$3xy,-xy$

Answer 1

Addition of like terms

When all the terms have different sign, add the coefficients of the positive and negative terms separately. Take the difference of these two results and prefix the sign of the greater coefficient.

Here the terms have different sign and the variable is $xy$

Therefore,

$$\begin{gathered} =3xy+(-xy) \\ =(3-1)xy \\ =2xy \end{gathered}$$