+118658 cos(x)= - 0.7. If x and y are complementary, what is sin(y)?
Think about this
You have sine(angle) and you have cosine(angle)
Did you ever stop to think about what the co stands for?
Co stands for complementary!
so cos(x)=sin(90-x) and sin(x)=cos(90-x)
in your question x+y=90 so y=90-x
you should be able to finish it now :)
