Question 203344
1. (2x² + 3x – 1) + (5x² - 5x – 5)
7x^2-2x-6 ans.

2. (2x² + 3x – 1) – (5x² - 5x – 5)
-3x^2+8x+4 ans.

3. (4x2y3z)(-3x3yz3)
-12x^5y^4z^4 ans.

4.  3x(2x – y) – 2y(3x + y)
6x^2-3xy-6xy-2y^2
6x^2-9xy-2y^2 ans.