# 8.5 Areas of Circles. What is  ? Investigation: A Taste of  p 332  = 3.14159265….. If C is the circumference and d is the diameter of a circle, then.

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8.5 Areas of Circles

What is  ? Investigation: A Taste of  p 332  = 3.14159265….. If C is the circumference and d is the diameter of a circle, then there is a number  such that C = _______. If d = 2r, where r is the radius, then C = _______. dd 2r2r

Area Investigation: Area Formula for Circles p 433 The area of a circle is given by the formula _______, where A is the area and r is the radius of the circle. A =  r 2

8.6 Any Way You Slice It Cut my pie into four pieces – I don’t think I could eat eight. YOGI BERRA

Definitions Sector, segment, annulus

Find the area of the shaded sector The sector is 45⁰ and the radius is 20 cm.

Find the area of the shaded segment The radius is 6 cm and it is an isosceles right triangle.

The shaded area is 14π cm², and the radius is 6 cm, what is the measure of the central angle?

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