Question

190 номер нужна помощь

Answer 1

1)21a²-(12a-5+21a²)=21а²-12а+5-21а²=5-12а
2)(x²+x-1)-(x²-x+1)=х²+х-1-х²+х-1=2х-2
3)-7x²+x+(x+6x²)-7х²+х+х+6х²=-х²+2х
4)(12-p²)+(p³+2p²-p+15)=12-5р²+р³+2р²-р+15=27-3р²+р³-р