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The AREA of a circle can be found using which formula? 2∏r ∏r2 SECTOR = part of the AREA A SECTOR of a circle is part of the AREA of the circle. SECTOR = part of the AREA A of a circle is part of the of the circle. sector ? area ? 180 ∘ SECTOR = part of the AREA A full circle is degrees... How large is the part ?? The angle measure of a full circle (360) Place the sector angle (central angle) OVER 180 ∘ SECTOR = part of the AREA A full circle is 360 degrees. How large is the part ?? 180 ? 360 ? 360 180 180 = ∘ 18 36 Reduce 180/360 to find what part of the area the sector is. = 180 ∘ A 180 degree sector is exactly one half the AREA of a circle. If the AREA of this circle was 42∏, the 180 degree SECTOR area would be half of that, ∏ A 120 degree sector is what part (fraction) of the full circle? ½ ⅓ ¼ 1/5 120 360 = 12 36 = A 120 degree sector is what part (fraction) of the full circle? 1 3 ⅓ A 90 degree sector is what part (fraction) of the full circle? ½ ⅓ ¼ 1/5 360 90 = 36 9 = A 90 degree sector is what part (fraction) of the full circle? 1 4 ¼ A 60 degree sector is what part (fraction) of the full circle? 1/4 1/5 1/6 6/6 360 60 = 36 6 = A 60 degree sector is what part (fraction) of the full circle? 1 6 1/6 Full Circle angle measure Central sector angle 72 ∘ A 72 degree sector is what part of the full circle? 360 ? 72 ? = 360 72 = 1 5 6cm SECTOR= Part of the AREA sector angle 360 360 * * ∏ 2 ∏r2 reduce the fraction 6cm SECTOR= Part of the AREA sector angle 360 360 90 * * * ∏62 ∏ ∏r2 = ∏ The 90 degree sector equals 9∏ cm2 The total AREA is ∏ cm2 9∏ 9∏ 9∏ 9∏ 6cm SECTOR= Part of the AREA sector angle 360 360 * * ∏ 2 ∏r2 reduce the fraction 6cm SECTOR= Part of the AREA sector angle 360 360 120 * * * ∏62 ∏ ∏r2 = ∏ The 120 degree sector equals 12∏ cm2 The total AREA is ∏ cm2 12∏ 12∏ 12∏ |