Circles

You worked out the areas and circumferences of circles when you did this worksheet in class.  Following on from that, we looked at arcs, sectors and segments.

A good explanation of how to work out arc lengths and the area of sectors is given here. 

Finding the area of a segment is a bit harder as we have to first find the area of the triangle (which we then subtract from the area of the sector to find the area of the segment).  In class we found the area of the triangle using ½absinC. Alternatively you could cut the triangle in half, use SOHCAHTOA to find the height and use ½ base x height.

Here’s the worksheet we did in class with answers.