Respuesta :

Provided that the triangle looks like this:

A| \  |   \  |    \  |     \  |      \ b|        \   20  |           \  |              \  |                \  |                 \  |_______40\C      a          B

Then using the the equation to solve for line segment AC (or b on the diagram):

sin(40) = b/20

b = 20 * sin 40
b = segment AC = 12.9 units
12.9 just took it on the quiz