For this case we must simplify the following expression:
[tex]3-2y-1 + 5x ^ 2-7y + 7 + 4x ^ 2[/tex]
We combine similar terms, taking into account that equal signs are added and the same sign is placed, while different signs are subtracted and the sign of the major is placed.
[tex]3-1 + 7-2y-7y + 5x ^ 2 + 4x ^ 2 =\\9-9y + 9x ^ 2[/tex]
Answer:
[tex]9-9y + 9x ^ 2[/tex]