Question

2а+(3а-8b) 
(5-2x)-(7+10x)

Answer 1

2a+3a-8b=5a-8b
5-2x-7-10x= -12x-2

Answer 2

2а+(3а-8b)=2а+3b-8b=5a-8b;

(5-2x)-(7+10x)=5-2x+(-7-10x)=5-2x-7-10x=-12x-2.