Question

giúp với ạ

Answer 1

\(a^2 + b^2 + c^2 + 42 = 2a + 8b + 10c \)

\(<=>a^2 - 2a + 1 + b^2 - 8b + 16 + c^2 - 10c + 25 = 0\)

<=> \((a - 1)^2 + (b - 4)^2 + (c - 5)^2 = 0\)

<=>\(\left\{{}\begin{matrix}\left(a-1\right)^2=0\\\left(b-4\right)^2=0\\\left(c-5\right)^2=0\end{matrix}\right.\) <=> \(\left\{{}\begin{matrix}a=1\\b=4\\c=5\end{matrix}\right.\)