"I did not get the answer I was hoping for."
Translation:Jeg fikk ikke det svaret jeg håpte på.
The Norwegian answer says 'det svaret' rather than 'svaret', but the English translation says 'the answer' rather than 'that answer'. Is this an idiomatic thing?
I think it is the phrase "fikk ikke det/den", it correlates to "didn't get the". I didn't get the result I was hoping for. Jeg fikk ikke det resultatet jeg håpte på. You won't get the impression you are hoping for. Du vil ikke få det inntrykket du håper på. She didn't get the feedback she was hoping for. Hun fikk ikke den tilbakemeldingen hun håpte på.
The expectation is a certain (but not specified) answer/result/etc, not just any sort of answer/result/etc. A relative sentence, comparing (not this one, but that). Den/det is here an old accusative leftover, the same form used when pointing out something, but in English it turns into that (that jacket/den jakken).