\[(x - 4)(x + 9) > (x + 12)(x - 7)\]
\[x^{2} + 9x - 4x - 36 > x^{2} - 7x + 12x - 84\]
\[x^{2} + 9x - 4x - x^{2} + 7x - 12x > - 84 + 36\]
\[0 > - 48 \Longrightarrow верно.\]