\[x² - 4x + y^{2} + 2y + 5 \geq 0\]
\[(x - 2)^{2} + (y + 1)^{2} \geq 0\]
\[(x - 2)^{2} \geq 0;\ \ \]
\[(y + 1)^{2} \geq 0 \Longrightarrow верно.\]