Hello David,
Just to let you know, I was able to modified your formula as follows:
In E51
=IF(OR(A51="",B51="",C51=""),0,DEGREES(ATAN(A51*SI N(RADIANS(C51))/(B51-A51*COS(RADIANS(C51))))))

Thanks again
Serge

"David Biddulph" wrote:

"Serge" wrote in message
...

"David Biddulph" wrote:

"Serge" wrote in message
...
I'm working on another Triangle solution which I have a bit of trouble
with.
In E51=A51*SIN(RADIANS(C51))/B51-(A51*(COS(RADIANS(C51))))
To represent: tan A = a x sin C / b - (a x cos C)
a=25.0 in A51
b=21.5407 in B51
Angle C=42.03 Degrees in C51
Answer should be 79.935 degrees.

could you help with this one as well?

You need:
tan A = a x sin C / (b - (a x cos C)), noting the brackets around the b -
(a
* cos C) [and of course you don't strictly need the brackets around a *
cos
C].

E51=A51*SIN(RADIANS(C51))/(B51-A51*COS(RADIANS(C51)))
Your answer is =DEGREES(ATAN(E51)) which gives the 79.935 you were
looking
for.

Hello David,
Thanks for your reply.
It's not working for me. I copied the formula as it was written and pasted
it E51 and the answer I got was 5.63 degrees.
Is there something I'm missing?

Please read my reply again.

What you got in E51 was *not* 5.63 degrees. It was 5.63. E51 is the value
of tan A in your explanation above.
If you want the angle A in degrees, you need =DEGREES(ATAN(E51)) which gives
79.935.
--
David Biddulph