Question 717445
If it's really {{{(a^2+4a^2)+(a^3-5a^2+7a)}}}
{{{a^2+4a^2=5a^2}}}
It is strange that it would be written as {{{(a^2+4a^2)}}} and it made me suspect that there was a typo.
The two sets parentheses can be removed without changing the result, because they are preceded by a + sign (or at the start of the expression).
{{{(a^2+4a^2)+(a^3-5a^2+7a)=5a^2+a^3-5a^2+7a=a^3+7a=a(a^2+7)}}}
I would say that {{{a^3+7a}}} or {{{a(a^2+7)}}} is as simplified as you can get.
Depending on what I need to do with the expression afterwards, I would choose one or the other simplified version.