It is true that only two equations in three unknowns has a infinite number of solutions and they must be written as parametric equations.
What do you get if you put \(\displaystyle x= -\frac{2414}{23}+ 2520t\), \(\displaystyle y= -\frac{980}{23}+ 1176t\), and \(\displaystyle z= 924t\) into the equations \(\displaystyle 9x- 24y+ 6z= 78\) and \(\displaystyle 28x+ 28y- 112z= -1064\)?