Find the coordinates of the point whose polar coordinates are (20,140degrees).

r=20
0=140
x=r cos (o)
y=r sin (o)
x=20 cos (140)
y=20 sin (140)
x=20 (-0.7660)= -15.32
y=20 (0.6427)= 12.85

(-15.32, 12.86)
on my answer on my paper, I left off the - and the ) at the end. She pointed at the ( at the beginning but she didn't add the negative sign for 15.32 so I'm confused on whether I got it wrong just because I left off the parenthesis at the end or the answer isn't (-15.32, 12.86)

I answered it the last time you posted it.

I will leave it up to you to find it, think it was sometime this afternoon.

Your correct answer is (-15.32,12.85)

leaving a negative sign off, is a major error,
forgetting a bracket at the end I would consider "bad form"
I also would not give full marks if your sollution contained "bad form".

Thanks. I posted this question 4 times titled math, math repost, math repost, and this one.

You must be thinking of the other question about writing the standard form of the equation of the circle but oh well.

The answer should be (-15.32, 12.86), not (-15.32, 12.86). The negative sign is necessary because cosine (140 degrees) is negative. The correct and complete answer is (-15.32, 12.86). The parenthesis are typically used to indicate an ordered pair, but it is acceptable to just separate the coordinates with a comma. In this case, the parenthesis are not required. So, you didn't get it wrong just because you left off the parenthesis.