1. Warm-Up  Multiply.  1.89 x 97  2.234 x 76  3.837 x 34  4.38 x 28

2. 10.7 Circumference and Area: CIRCLES Pre-Algebra

3. Sir Cumference and the Dragon of Pi Circumference of Circles

4. Parts of a circle!  Circumference The distance AROUND the circle  Center The given point in the very middle  Radius The distance from the CENTER to ANY point on the circle  Diameter The distance across the circle THROUGH its center

5. Circumference  Formulas C = 2 r C = d  C is Circumference  is 3.14  r is radius  d is diameter

6. Area  A = r 2  A is the Area  Pi is 3.14  R is the radius squared

7. SHOW ALL OF YOUR WORK EVERY TIME!!!!!  FORMULA  WORK  ANSWER  UNITS

8. Examples  1.Find the circumference and area of the circle if: r = 2 cm

9. Examples  2.Find the circumference and area of the circle if: d = 6 in

10. Find the circumference and area to the nearest tenth.  3. 12 in.

11. Find the circumference and area to the nearest tenth.  4. 7.1 m

12. Find the circumference and area to the nearest tenth.  5. 11 ft

13. Find the circumference and area to the nearest tenth.  6. 8.3 cm

14. 10.7 Study Guide and Intervention Write ALL formulas EVERY time and SHOW all work!

15. Homework! Write ALL formulas EVERY time and SHOW all work!

16. Do not just Guess!!! Show WORK!!!!