SOLUTION: If sin θ = 0.42 then what does sin (180+θ) equal? I recently did a trigonometry test and this was one of the questions on the non-calculator section. I know how to work

Algebra ->  Trigonometry-basics -> SOLUTION: If sin θ = 0.42 then what does sin (180+θ) equal? I recently did a trigonometry test and this was one of the questions on the non-calculator section. I know how to work      Log On


   

Question 617824: If sin θ = 0.42 then what does sin (180+θ) equal?
I recently did a trigonometry test and this was one of the questions on the non-calculator section. I know how to work it out using a calculator but I'm not sure how to do it without one.
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
If sin θ = 0.42 then what does sin (180+θ) equal?
Use sin addition formula to solve
sin(s+t)=sin s cos t+cos s sin t
=sin180cosθ+cos180sinθ
=0*cosθ+(-1)(.42)
=-.42