\[h = 24t - 5t^{2}\]
\[\ m = - \frac{24}{10} = - 2,4;\]
\[n = 24 \cdot ( - 2,4) - 5 \cdot 5,76 =\]
\[= 57,6 - 28,8 = 28,8.\]
\[24t - 5t^{2} = 0\]
\[t(24 - 5t) = 0\]
\[t = 0;\ \ \ 5t = 24\]
\[\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ t = 4,8.\]
\[через\ 4,8\ с\ после\ броска\ мяч\ \]
\(упал\ на\ землю.\)