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# How do i find angle x watch

1. (Original post by User23)
All I did was just do x/360 x 12 pi = 14.5929....
Then I made x the subject of the formula
OK, if you've not come across radians.

Circumference is 2*pi*r, or pi*d

And multiply by x/360 for the arc length subtending an angle of x degrees.

You've used pi*r.

You're missing a factor of 2.
2. (Original post by ghostwalker)
OK, if you've not come across radians.

Circumference is 2*pi*r, or pi*d

And multiply by x/360 for the arc length subtending an angle of x degrees.

You've used pi*r.

You're missing a factor of 2.

Oh so is the answer 84 degrees???
3. (Original post by User23)
Oh so is the answer 84 degrees???
That's what I make it.
4. (Original post by User23)
Oh so is the answer 84 degrees???
Can't be 84 degrees if the diagram is correct, because it looks like angle x is bigger than 90 degrees.

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5. (Original post by Ishan_2000)
Can't be 84 degrees if the diagram is correct, because it looks like angle x is bigger than 90 degrees.

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I don't think the diagram is drawn to scale though.
6. (Original post by Ishan_2000)
Can't be 84 degrees if the diagram is correct, because it looks like angle x is bigger than 90 degrees.

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As User23 said, diagrams aren't always accurate. Diagram is actually misleading.

You could make a model if you want an additional check.
7. (Original post by ghostwalker)
As User23 said, diagrams aren't always accurate. Diagram is actually misleading.

You could make a model if you want an additional check.
I guess diagrams aren't always correct, as User23 said.
But, they must be or should be vaguely correct. Maybe just an awful diagram.
8. I used a different approach and got the same answer, it's easier to use the methods above though.

Arc length = 5.6 * pi
Area of sector = 0.5 * arc length * radius = 0.5 * arc length * 12

Area of sector = x/360 * (pi * r^2)
x = 360A / pi * r^2)
x = 360A / 144 pi

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