For this case we have the following expression:
[tex](xy-3y ^ 2 + 5xy ^ 2) - (- xy + 3xy ^ 2-3y ^ 2) =[/tex]
We apply distributive property considering that:
[tex]- * + = -\\- * - = +[/tex]
Rewriting the expression we have:
[tex](xy-3y ^ 2 + 5xy ^ 2) + xy-3xy ^ 2 + 3y ^ 2 =\\xy-3y ^ 2 + 5xy ^ 2 + xy-3xy ^ 2 + 3y ^ 2 =[/tex]
We add similar terms taking into account that:
Equal signs are added and the same sign is placed.
Different signs are subtracted and the major sign is placed.
[tex]xy + xy-3y ^ 2 + 3y ^ 2 + 5xy ^ 2-3xy ^ 2 =\\2xy + 2xy ^ 2[/tex]
Answer:
[tex]2xy + 2xy ^ 2[/tex]
