Найдите разность арифметической прогрессии, если x_5=-4; x_14=50.

\[x_{5} = - 4;\ \ x_{14} = 50;\ \]

\[x_{5} = x_{1} + 4d;\text{\ \ }x_{1} = x_{5} - 4d\]

\[x_{14} = x_{1} + 13d;\ \ x_{1} = x_{14} - 13d\]

\[x_{5} - 4d = x_{14} - 13d\]

\[- 4 - 4d = 50 - 13d\]

\[9d = 54\]

\[d = 6.\]