Sine Rule Function

[Miles_Ford]

I've created a function to solve for a missing side or angle for a non-right angled triangle using the Sine Rule. The basic version works fine:

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SineRule[a_, A_, b_, B_] := N[Solve[a/Sin[A] == b/Sin[B], x][[1, 1, 2]]]

The students just enter in the unknown side or angle as x.

But, with this code the angle results are in radians which my students aren't familiar with. So I wrote this code to convert the radians to degrees if it's an angle they're looking for:

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SineRule[a_, A_, b_, B_] := If[a == x || b == x, N[Solve[a/Sin[A] == b/Sin[B], x]][[1, 1, 2]], N[Solve[a/Sin[A] == b/Sin[B], x][[1, 1, 2]] 180/\[Pi]]]

Now when I use this to solve a missing side it's fine.

But when I use it for an unknown angle it just splits the code back at me:

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If[24.5==x\[Or]16==x,N[Solve[24.5/sin(80 \[Degree])==16/sin(x),x]][[1,1,2]],N[(180 Solve[24.5/sin(80 \[Degree])==16/sin(x),x][[1,1,2]])/\[Pi]]]

Love some input on what I'm doing wrong here.

[Miles_Ford]

Solved my own problem, needed === up in the If statement rather than ==.

The full working versions for the Sine Rule and Cosine Rule then are as follows:

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SineRule[a_, A_, b_, B_] :=
If[a === x || b === x, N[Solve[a/Sin[A] == b/Sin[B], x]][[1, 1, 2]],
  N[Solve[a/Sin[A] == b/Sin[B], x][[1, 1, 2]] 180/\[Pi]]]

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CosineRule[a_, b_, c_, C_] :=
If[C === x,
  N[Solve[c^2 == a^2 + b^2 - (2 a b Cos[C ]), x]][[2, 1, 2]] 180/\[Pi],
  N[Solve[c^2 == a^2 + b^2 - (2 a b Cos[C ]), x]][[2, 1, 2]] ]

Simply use x as the unknown.