Warmup l Find the circumference and area of

Warm-up l Find the circumference and area of the following circles: R = 7 ft D = 20 in

Arc Length & Sector Area Unit 5. 3

Finding Arc Length l Arc length is a piece of the circumference. xo r

Calculate the length of the arc 750 r = 8 cm cm Arc Length = Multiply your answer by the fraction of the circle you do have.

YOUR TURN! Calculate the length of the arcs 2750 r = 3. 5 cm 850 P = 17. 80 cm 3160 r = 6 cm r = 8 cm P = 8. 90 cm P = 54. 12 cm r = 4 cm 200 P = 1. 40 cm

Given the ‘other’ angle. Calculate the arc length of the RED sector First, find the angle we NEED. r = 7 cm 670 cm Arc Length =

YOUR TURN! Arc = 42. 73 cm 88 o r = 9 cm

Calculate the area of the sector 750 r = 8 cm cm 2 Sector Area = Multiply your answer by the fraction of the circle you do have.

Calculate the area of the sectors below: 2750 r = 3. 5 cm 850 3160 r = 6 cm A = 29. 40 cm 2 r = 8 cm A = 26. 70 cm 2 r = 4 cm 200 A = 2. 79 cm 2 A = 176. 49 cm 2

Given the ‘other’ angle. Calculate the sector area of the RED sector First, find the angle we NEED. r = 7 cm 670 cm Sector Area =

This is a diagram of a pond, with a concrete path around it. If the diameter of the pond is 5 feet, and the path is 1 foot wide, what is the area of the concrete?

The width of a CD is 2 cm, and the diameter of the center hole is 4 cm. The case is 8 cm wide and tall. What area of plastic is seen?