Answer :
[tex]5a-[3b-\{4a-(5b-6a-7b)\}]\\\\=5a-[3b-\{4a-(-6a-2b)\}]\\\\=5a-[3b-\{4a+6a+2b\}]\\\\=5a-[3b-\{10a+2b\}]\\\\=5a-[3b-10a-2b]\\\\=5a-[b-10a]\\\\=5a-b+10a\\\\\boxed{=15a-b}[/tex]
Corrected question :
- 5a - [3b- {4a - (5b - 6a - 7b)}]
Solution :
First let us solve parentheses or round brackets,
=> 5a - [3b - {4a - (5b - 7b- 6a)}]
=> 5a - [3b - {4a - (-2b - 6a)}]
Now solving for curly bracket,
=> 5a - [3b - {4a + 2b + 6a}]
=> 5a - [3b - {10a + 2b}]
Now solving for box bracket,
=> 5a - [3b - 10a - 2b]
=> 5a - [b - 10a]
=> 5a - b + 10a
=> 15a - b
