If the system of equations
\[
x-2y+z=-4,\qquad
6x+y+kz=15,\qquad
39x-13y+hz=39
\]
has infinitely many solutions, then the locus of the point \((h,k)\) is a straight line. The \(x\)-intercept of that line is
Show Hint
If a system of three linear equations has infinitely many solutions, then one equation must be a linear combination of the other two.
\[
\boxed{
R_3=\lambda R_1+\mu R_2
}
\]
Comparing corresponding coefficients quickly gives the required relations.