# Need help calculating coordinates for a tangent point.

#### gixxerman1980

So let's say I know coordinates for D (-10171.62, 490.26) angle at that point is 75.52. Also, line EF is a section of a line that starts at -10249, 0 and ends at -10094.8, 7615.2. How do I find the coordinates for A?

BTW, the angle at A is 91.16

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#### skeeter

Math Team
So let's say I know coordinates for D (-10171.62, 490.26) angle at that point is 75.52. Also, line EF is a section of a line that starts at -10249, 0 and ends at -10094.8, 7615.2. How do I find the coordinates for A?

BTW, the angle at A is 91.16
Your image doesn't seem to match up with the info you provided.

line EF is a section of a line that starts at -10249, 0 and ends at -10094.8, 7615.2
If point E has coordinates (-10249, 0) and point F is (-10094.8, 7615.2), then point F's x-coordinate should be less than -10249. Note -10094.8 > -10249

BTW, the angle at A is 91.16
What angle at A? The angle at the intersection of the tangent line and radius at point A is 90 degrees.

I advise you to make a better sketch that fits your given information.

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#### gixxerman1980

Sorry, I found that image on google and thought it may be enough to show the point I'm trying to find coordinates for. I'll try to draw something that will be a little closer visually.

#### gixxerman1980

I know the drawing shows the known point on the circle looking more like it is at about 50 degrees, but I hope that is close enough.

#### skipjack

Forum Staff
Can you label all relevant points (A, D, E, F, etc.) and mark the known angles?

#### skeeter

Math Team
I'm not seeing the 75.52 degree angle by point D

#### sagar233

Nothing is clear with this image.

Can you plot all the known points with origin point first, with their labels?, then try to sketch circle & angles.