Question

а) (7а-b)-(5a-4b)+3(b-4a)=

б)-3(2x-y+7)+7(2x-6y+5)=

Answer 1

а)(7а-b)-(5a-4b)+3(b-4a)=7а-b-5a+4b+3b-4a=8a+6b
б)-3(2x-y+7)+7(2x-6y+5)=-6x+3y-21+14x-42y+35=8x-39y+14