Hello from MrBillDoesMath!
Answer:
x >= 7
Discussion:
x + 5 >= 12 => add -5 to both sides
x + 5 -5 >= 12 - 5 => as 5-5 = 0 and 12 =5 = 7
x >= 7
Thank you,
MrB
For any equation,

assume solution of a form, 
Which leads to,

Simplify to,

Then find solutions,

For non repeated real root y, we have a form of,

Following up,
For two non repeated complex roots
where,

and,
the general solution has a form of,

Or in this case,

Now we just refine and get,

Hope this helps.
r3t40
35% Just move the decimal place forward two places. That's how i LEARNED IT
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