The points R, T, and U lie on a circle that has radius 4. If the length of arc RTU is 4pi/3. what is the length of line segment RU?
a. 4/3
b. 8/3
c. 3
d. 4
e. 6
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A circle by definition contains 360. The length of an arc relative to the circle circumference is directly proportionate to the arc degree.
Let x be arc degree so
length of the arc/circumference of circle=x/360
(4pi/3)/2pi*r=x/360
since r=4(given)
there fore
x=60 degrees
so given that radius is 4 then from figure OR=4 and OU=4
2 sides are equal it is an isoceles triange
so the other angle is 60.
since 2 angles are 60 the other angle is also 60 so it an equaliatera triangle so all sides are equal so
RU=4
I think my explanation is too long. I have made a word attachment which contains a rough figure
Suggest me if iam wrong.
Thanks,
Sibbineni
Let x be arc degree so
length of the arc/circumference of circle=x/360
(4pi/3)/2pi*r=x/360
since r=4(given)
there fore
x=60 degrees
so given that radius is 4 then from figure OR=4 and OU=4
2 sides are equal it is an isoceles triange
so the other angle is 60.
since 2 angles are 60 the other angle is also 60 so it an equaliatera triangle so all sides are equal so
RU=4
I think my explanation is too long. I have made a word attachment which contains a rough figure
Suggest me if iam wrong.
Thanks,
Sibbineni
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