1. Unit 10: 2-Dimensional Geometry

2. Area of Polygons

3. Area Formulas Square Area = side 2 Triangle Area = base × height 2
Trapezoid
Area = height ×( base 1 + base 2 ) 2
Rectangle
Area = length × width
Rhombus
Area = diagonal 1 × diagonal 2 2
Parallelogram
Area = base × height
These must be memorized!

4. Area of Squares & Rectangles
Area = side 2
Area = (6) 2
Area = 36 square inches
Rectangles
Area = length × width
Area = 8 × 3
Area = 24 square inches

5. Bases and heights must be at right angles!
Area of Triangles
Bases and heights must be at right angles!
Right Triangle
Area = base × height 2
Area = 2 × 4 2
Area = 8 2
Area = 4 square cm
Triangle
Area = base × height 2
Area = 6 × 4 2
Area = 24 2
Area = 12 square cm
Triangle
Area = base × height 2
Area = 3 × 5 2
Area = 15 2
Area = 7.5 square cm

6. Area of Parallelograms & Rhombi
Area = base × height
Area = 9 × 7
Area = 63 square inches
Rhombus
Area = diagonal 1 × diaagonal 2 2
Area = 12 × 8 2
Area = 96 2
Area = 48 square units

7. Area = height ×( base 1 + base 2 ) 2
Area of Trapezoids
Trapezoid
Area = height ×( base 1 + base 2 ) 2
Area = 5 ×(7 +13) 2
Area = 5 ×(20) 2
Area =
Area = 50 square inches