1) (a-2) (a-1)-a(a+1) 2) (b-5) (b+10)+(b+6) (b-8) 3) (2c+3) (3c+2) - (2c+7) (2c-7) 4)...

Question

1) (a-2) (a-1)-a(a+1) 2) (b-5) (b+10)+(b+6) (b-8) 3) (2c+3) (3c+2) - (2c+7) (2c-7)
4) (3d+5) (5d-1) - (6d-3) (2-8d)
помогите плиз не могу решить

Answer 1

1)а^2-а-2а+2-а^2-а
-4а+2
2 (1-2а)