Crossword Help Forum
Forum Rules

https://en.wikipedia.org/wiki/Law_of_sines

Tonta, glad I could help.

T-trill for repeated 4 (8) T _ _ _ _ _ N _

Sorry, I don't have the answer to 4A - I did not mess around with
a 12 (6) N _ _ _ E _

Neither do I have the answer to 12 - Go from 12 to 13, or 12 to 9?
(4)

But the answer to 13 is "Angle".

And so on ......... You can see my difficulty.

trolling perhaps for the 1st one??

have you got 9?

A random thought regarding 4 A - and it could be totally wrong! - but my first thought, with your letters, was Napier, the mathematician.

No, Tevor, sorry, I don't have 9.

But 4A I did not mess around with a 12 (8) seems to be an
anagram
- ADDITION.

Then 12A Go from 12 to 13, or 12 to 9? (4) R _ L _ (L from your
Trolling) 13 is Angle

I deliberately didn't give the clue for 9A - you can see why!

9A 27, for example, but not 19 (6) N _ O _ E ( O from Trolling)

27 is Zero, 19 don't have it.

I wish I could scan in the whole crossword.

9A should be N _ O _ E _

it is addition (you gave it as 6 letters)

btw. i doubt trolling is right if 4 is addition.