Question 402258
1)
a+(3a-2b)-(4a-3b)
a+3a-2b-4a+3b
=b
a's cancil
3)
7a+[4a-6b-(8a+2b)]
7a+[4a-6b-8a-2b]
7a-3a-8b
=4a-8b
you try the others
follow the order of operations