Question 443382
{{{(5a - 3a^2) + (8 + 7a)}}}
{{{5a - 3a^2 + 8 + 7a}}}
Rearrange order: {{{5a + 7a - 3a^2 + 8}}}
Combine like terms: {{{12a - 3a^2 + 8}}}
Rearrange order: {{{-3a^2 + 12a + 8}}}
CANNOT SIMPLIFY FURTHER
Therefore, your final answer is {{{-3a^2 + 12a + 8}}}