(3x4 + 4x3 – x2 + x – 5) + (5x4 – 8x3 + 4x2 + 2x + 4)

1.

x4 – x2 + 4 + 3x3 – 4x2 – x

2.

(5x3 + 7x2 – 2x – 7) – (x3 + 3x2 + 6x – 7)

3.

7a2b – 3ab2 + a3 – 4ab2

4.

(8a3b + 6a2b2 – 4ab3) – (5a2b2 + 3ab3)

5.

(12r3t3 – 11r2t3 + 15rt3) – (21r4t3 – 12r3t3 – 11r2t3)

6.

7 – x5y2 – 3xy4 + x3y3 – 15 + 2xy4 – x5y2 + x4y5

7.

(13r5 + 12r3 – r2 – r) + (r5 – 9r4 + 5r3 – 10r)

8.

(12a3 – 7a2 + 2a) – (8a3 + 5a2 – a) + (2a2 – a + 15)

9.

(11c + 5c2 – 7) – (12 – 8c + c2) – (4c2 – 12 + 14c)

10.