Are "tener que" and "tener de qué" interchangeable?

[createdamadman]

I have the sentence below and it is the second time I've seen the "tener de qué" form used in the story I'm reading. Could "tener que (tienes que)" be used here as well, or are there times when "tener de qué" must be used?

"No tienes de qué preocuparte."

[wrholt]

"No tienes de qué preocuparte" = "You have nothing to worry about."

"No tienes que preocuparte" = "You don't have to worry."

"Tener que" and "tener de qué" are not synonymous expressions, and the surface meanings of these two sentences are different.

[Rusty]

Cross-posting:

These phrases are not interchangeable, since they have two distinct meanings.

tener que (hacer algo) = estar obligado (a hacer algo) = have to do something / must do something

tener de qué (infinitivo) = tener por qué (infinitivo) = have a reason (for doing something)


These are affirmative examples. Yours are negative (the opposite of what I wrote).