Respuesta :

JuanitaM
Make notes of these
sin = opposite/hypotenuse
cos = adjacent/hypotenuse
tan = opposite/adjacent

in your problem you have opposite of 22 degrees and adjacent - so you can only use tan

tan 22 = x/18
solve for x (which is your BC)
check the picture below.

make sure your calculator is in Degree mode.
Ver imagen jdoe0001