1.3b+(5-7b) 2.-(8c-4)-4 3.3(8a-4)+6a 4.7p-2(3p-1) 5.x(x-(2x-4)) 7 класс.
1) 3b+5-7b=+5-4b 2)-8c+4-4=-8c+0 3)24a-12+6a=18a-12 4)7p-6p+2=1p+2 5)х(х-(2х-4)=x(x-2x+4)=2x-2x+4x=4x
1. 3b+5-7b=-4b+5; 2. -8c+4-4=-8c; 3. 24a-12+6a=30a-12; 4. 7p-6p+2=p+2; 5. x(x-2x+4x)=x²-2x²+4x²=3x².