Answer:
6. 9^2+4x-1
7. 7x - 3 cm
8. -6x^2+3x-4
9. 4x+10y+4z
10 13x^2 - 2x
11. -5x^2 - 8x - 16
Step-by-step explanation:
6. (13x^2+x-3)-(4x2-3x-2) = 9x2+4x-1
7. x +4+2x+1+4x-8
= 7x-3 cm
8. (-8x^2 + 8x + 1) + (14x^2-11x+3)
10. (8x^2+x)-(-5x^2+3x)
11. (-x^2-6x+5) - (4x^2+2x+11)
