Question

Помогите!!!!!!!!!!!!!!!!!!!

Answer 1

Ответ:

1) 0,25a²-2ab+4b²

2)a²-9/16b²

2

2(x²+2x+1)-(x²-9)=7+x²;

2x²+4x+2-x²+9-7-x²=0;

4x+11-7=0;

4x=-4;

x= -1