There are positive real numbers \(x\) and \(y\) which solve the equations \[2x + ky = 4, \qquad x+y = k\] for
all values of \(k\);
no values of \(k\);
\(k=2\) only;
only \(k>-2\).
There are positive real numbers \(x\) and \(y\) which solve the equations \[2x + ky = 4, \qquad x+y = k\] for
all values of \(k\);
no values of \(k\);
\(k=2\) only;
only \(k>-2\).