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point P on a circle

How do I calculate point P on a circle when I have the following information:
Radius=7
Arc Length=3
Angle in degrees=0.42857
Angle in rounded degrees 25

Comments

I have a question about your question.
 
You say - Angle in degrees=0.42857 Angle in rounded degrees 25
 
How can these both be true?    Is one of these supposed to be radians?
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2 Answers

The fact that the arc length is 3 and he radius is 7 is a complete specification of the size of the angle
which is length of arc/length of circle =angle in radians /2π
angle in radians=2π×3/(2π×7)=3/7 radians = (180/π)×3/7 degrees=24.55533408
Either start at the x-axis and go up 3/7 radian or calculate the rectangular coordinates as
x=7cos(3/7) y=7sin(3/7) with radians set
x=7cos(24.55533408) y=7sin(24.55533408) with degrees set
 
I worked out 250 is approximately 0.4 radians so I am going to solve that way.
 
Consider the line from the center (0,0) of the circle to the point like a vector.
 
X = r cos(θ) =
Y = r sin(θ) =
 
So put your calculator in radians mode
   and plug the values into the equations using θ = 0.42857 rad.
 
Or put your calculator in degrees mode
    and plug the values into the equations using θ = 25 degrees.
 
There are other ways and equations to use to get the answer, but those are to me
the easiest to learn; and they will be useful when you take physics too.
 
Important note: Those equations always work, but Only when you use the angle to the + x axis.  So if you are given a different angle use your geometry of a circle 3600, a line 1800, and a right angle 900 to find the angle to the + x axis - then proceed.