1. Lesson 11-1 Areas of Parallelograms

2. Vocabulary base – the horizontal distance of the parallelogram (bottom side) height – the vertical distance of the parallelogram area – the amount of flat space defined by the figure (measured in square units) perimeter – once around the figure

3. Area of Parallelograms AB CD h Parallelogram Perimeter Add length of all four sides P = AB + DB + DC + CA Parallelogram Area A = h · b h is height b is base (AB or CD) (similar to a rectangle) AB CD b

4. Example 1: AB CD 10 15 12 Find the perimeter and area of parallelogram ABCD 12

5. Example 2: MN PO 6 15 10 Find the perimeter and area of parallelogram MNOP 9 10

6. Example 3: DE GF 27 60° Find the perimeter and area of parallelogram DEFG 21 h

7. Example 1-2a The Kanes are planning to sod some parts of their yard. Find the number of square yards of grass needed. HINT: 1 sq yd = 9 sq ft To find the number of square yards of grass needed, find the number of square yards of the entire lawn and subtract the number of square yards where grass will not be needed. Grass will not be needed for the vegetable garden, the garage, or the house and walkways. e EXAMPLE 4:

8. The Wagners are planning to put hardwood floors in their dining room, living room, and kitchen. Find the number of square yards of wood needed. EXAMPLE 5:

9. Summary & Homework Summary: – The area of a parallelogram is the product of the base and the height Homework: – pg 598 (3-5, 10-17 omit 15, 26, 28)