Can someone please help 20b,c,d (1 Viewer)

[kpad5991]

https://imgur.com/gallery/mzcbP

 

[fan96]

b) Use the formula for the area of a sector



c) Use the formula for length of an arc



Remember that must be in radians for those two formulae.

d) Use the alternate formula for area of a triangle



(or alternatively, find the perpendicular height of the triangle with Pythagoras' theorem)

and you can answer the question using the result of b)

All of these formulae are on the reference sheet, by the way.