SOLUTION: PLEASE HELP ME SOLVE THIS TRIGONOMETRIC FUNCTIONS: sin 205degree the possible answers are: a)sin155degree b)sin25degree c)-sin25degree

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Question 236971: PLEASE HELP ME SOLVE THIS TRIGONOMETRIC FUNCTIONS:
sin 205degree
the possible answers are:
a)sin155degree
b)sin25degree
c)-sin25degree
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
the answer is - sin 25 degrees.

205 - 180 = 25 degrees in quadrant 3

in quadrant 3 the sin = opposite divided by hypotenuse.

the opposite is the vertical line parallel to the y-axis going in a downward direction so the opposite side is minus.

the hypotenuse is always positive.

opposite / hypotenuse = -/+ = -

if you use your scientific calculator, sin 205 shows up at -.422618262

- sin 25 shows up as -.422618262

they are equivalent.