noko

[Anonymous No.2486475]

an arc subtends an angle of 1 radian at the centre of a circle, and a sector of area 72cm is bounded by this arc and the two radii. Find the radius of the circle.

any idea how to do this? Or what the diagram looks like? Thanks

[EK !D96TK2PSsI No.2486485]

>a sector of area 72cm
you best mean <span class="math"> 72 cm^2 [/mth] nigga...[/spoiler]

[EK !D96TK2PSsI No.2486491]

>a sector of area 72cm
you best mean <span class="math"> 72 cm^2 [/spoiler] nigga...

[Anonymous No.2486497]

S=R*theta

[Anonymous No.2486502]

>>2486491

Why yes I do. Thank you for correcting

an arc subtends an angle of 1 radian at the centre of a circle, and a sector of area 72cm2 is bounded by this arc and the two radii. Find the radius of the circle.

any idea how to do this? Or what the diagram looks like? Than

[EK !D96TK2PSsI No.2486510]

>>2486502
*then.

...i'll fucking kill you.

[Anonymous No.2486513]

radius=12

72=(1rad*r^2)/2 =12

[Anonymous No.2486519]

>>2486513

what formula did u use and why / by 2

[Anonymous No.2486534]

>>2486519
http://www.mathwords.com/a/area_sector_circle..

the first formula

[Anonymous No.2486551]

>>2486534
>>2486534
>>2486534

Why thank you

[Anonymous No.2486587]

ok guys new question pls


The chord AB of a cilrcle subtends an angle of 60 degrees at the centre. Find the ratio of the lengths of the cord AB to arc AB

[Anonymous No.2486608]

>>2486587
Arc AB=((2piABradius)/360)*60) ?

[Anonymous No.2486633]

>>2486608

From which equation?

[Anonymous No.2486644]

>>2486633
I guessing

(arclength)=((2pi*Radius)/360)*60

[Anonymous No.2486658]

>>2486644

but why u divide by 360 n times by 60

[Anonymous No.2486667]

But it says work out the ratio :S

[wcrc oumag No.2487697]

AB/arcAB=2*sin(ang/2)/ang
ang=60°=π/3:
AB/arcAB=2*(1/2)/(π/3)=3/π