pke caraa k pliss bsk d kumpul !! yang nmr (11. 12 , 14 , 15)

11. -5x+8y-(4x-3y) = -5x+8y-4x+3y = -9x+11y (b)
12. 8-6a-6b+6a-2 = -6b+6 (c)
14. 8p^2-4p-12p+6 = 8p^2-16p+6 (b)
15. 2a^3-3a+5+(-3a^2-2a-2) = 2a^3-3a+5-3a^2-2a-2 = 2a^3-3a^2-5a-3 (d)