Law of Sines

You can always use pythagorean theorem as a shortcut.

a/sin(A) = b/ sin(B) = c/sin(C)

a given.
A given.
b given.
B unknown.

a/sin(A) = b/ sin(B)
sin(B)*a/sin(A) = b
sin(B) = sin(A)*b/a
B = asin( sin(A)*b/a )

c given.
C unknown.

A+B+C = 180
C=180-A-B
C=180-36-asin( sin(A)*b/a )

a/sin(A) = c/sin(C)
sin(C)*a/sin(A) = c
c = sin(C)*a/sin(A)

[input]a=4; b=3; A=36; c = sin( 180-36-asin( sin(A)*b/a ) ) * a / sin( A )[/input]

EisenhowerStudent:

You can always use pythagorean theorem as a shortcut.

well, the triangle might not have a 90° angle...