proper usage and meaning of わけがない

[Chronitsch]

Hei there, topic says it all in short

What is the meaning of わけがない and where do I need it

As an example sentence I have:
映画が大好きな長谷川さんが、この映画を、見に行かないわけがない。

Which I would translate to: The film loving Hasegawa goes to watch this movie.

But wouldn't there be an easier approach than that, does it maybe say he plans to or he doesn't plan to

help me please ^^

[Javizy]

映画が大好きな長谷川さんが、この映画を、見に行かないわけがない。

There is no reason that film-loving Hasegawa would not go to see this film.
That movie buff Hasegawa would never miss this film!

わけがない, literally 'there's no reason' means something like it's not reasonable to think that something will happen or is possible. It expresses your own feelings. You'd probably translate it as something like 'there's no way; ...would never; can't possibly'.

[Chronitsch]

ok thank you

with that said, if we would leave out the nai infront of wakenai (I know the sentence wouldn't make sence afterwards) it would mean something like There is no reason he would go see the film?


so if ngeative+wakenai = There is no reason he does not whatever
and if positive+wakenai = There is no he does whatever

?
short no + no = yes / yes + no = no ?

I get confused when this is used in a conversation like:
Student says Theres no way we are able to do this until tomorrow
and Teacher answers there is no way you are not able to do this, because we did it.

Japanese is complicated from time to time ^^