Unit 8  Circles & Geometry
Learning Outcomes
At the end of this unit, students should be able to: • Derive an approximation for pi (≈3.14 or 22 7 ) by gathering data and comparing the circumference to the diameter of various circles, using concrete materials or computer models • Approximate pi as 3.14 and 22 7 • Solve practical problems involving circumference and area of a circle when given the length of the diameter or radius • Solve practical problems involving area and perimeter of triangles and rectangles 
Essential Questions:
•What relationships are there among area, perimeter, and circumference? • How can the patterns of decomposing and recomposing shapes help derive formulas for geometric measurement? • What are the relationships among the parts of a circle? • What role does estimation play in solving problems? 
Vocabulary
center point
radius diameter circumfrence 
area
perimeter pi 
right triangle

Formulas for figuring circles
Diameter
Radius

2r = d
6r = C ; 1/2 d = r

Area of a circle

pi(r) squared = area of a circle

Perimeter

Distance around the outside of a shape

Area

The space inside the shape.
