a) (6a²+2a+1)-(-3a²-2a+5) = 6a²+2a+1+3a²+2a-5 =
= 9a²+4a-4
b) (12,5m²-1,25n²-1,6)-(2,25m²+3,75n²+2,4) = 12,5m²-1,25n²-1,6-2,25m²-3,75n²-2,4 =
10,25m²-5n²-4
c) (1,5x²y-0,75x²-15)-(0,4x²y-2 2/3 - 0,125x²) =
1,5x²y-0,75x²-15-0,4x²y+2 2/3 + 0,125x² =
1,1x²y-0,625x²-2 2/3
a) 5x+(2x-7)-9x-(-3x+8)+20-8x =
5x+2x-7-9x+3x-8+20-8x = -7x+5
b) -5x+(-2y+4x)-(7x-8y)-x+(2-6y) =
-5x-2y+4x-7x+8y-x+2-6y = -9x+2
c) -9z-(4-3z)-8y-(-7z+8y)+(-2y-7) =
-9z-4+3z-8y+7z-8y-2y-7 = z-11-18y
__________
mogą być jakieś błędy, bo liczyłam na szybko w pamięci
