2017 xy-2xy= _____

(xy)^-2*(xy)^2 =______

The Value of the Expression : 6xy-2xy+1= ......

Simplify : 7xy - 3xy - 6xy + xy - 5xy

xy^(2)- yz^(2)-xy +z^(2) =_____

Simplify the following : 7xy - 4xy - 3xy - 11 xy + 5xy - xy

Fill in the blanks: 3xy^2+4xy-2x^2y+9=3xy^2+9- _______

State true or false : 3xy,-2xy are like terms.

Add : 7xy , 2xy , - 8xy

At the end of the year 2016, the population of villages Kovad, Varud, Chikkali is 5x^2-3y^2 , 7y^2+2xy and 9x^2+4xy respectively. At the beginning of the year 2017, x^2+xy-y^2 , 5xy and 3x^2+xy persons from each of the three villages respectively. went to another village for education then what is the remaining total population of these three villages?