Determine Whether the Ordered Triple Is a Solution of the System

True/False

Determine whether the ordered triple is a solution of the system of equations. $$\left\{ \begin{aligned}4 x + y - z & = 0 \\- 8 x - 6 y + z & = - \frac { 7 } { 4 } \\3 x - y & = - \frac { 9 } { 4 }\end{aligned} \right.$$ $$\left( \frac { - 1 } { 2 } , \frac { 3 } { 4 } , \frac { - 5 } { 4 } \right)$$