CH.7 Flashcards
Units in areas are
Squared
Area Postulate
Corresponding to every bounded region is a unique positive number, known as the area of that region
≅ Figure => = Area Postulate
If 2 closed plane figures are ≅, then their areas are =
Area Addition Postulate
The area of one closed plane figured union-ed with another closed plane figure is equal to the sum of their areas
Area of a Parallelogram
A = bh
Area of a Square and Rhombus
A = s²
Area of a Triangle
A = 1/2bh
Perimeter
- Sum of the lengths of all sides of the polygon
- has a single unit of measure
Perimeter of Scalene, Isosceles, and Equilateral Triangles
Scalene: P = a + b + c
Isosceles: P = 2a + b
Equilateral: P = 3a
Perimeter of Quadrilateral, Rectangle, Square/Rhombus, and Parallelograms
Quadrilateral: P = a + b + c + d
Rectangle: P = 2b + 2h
Square/Rhombus: P = 4s
Parallelogram: 2b + 2s
Heron’s Formula for Triangles
A = √[s(s-a)(s-b)(s-c)]
S: Semiperimeter
Area of a Trapezoid
A = 1/2h(b1 + b2)
Area of a Kite
A = 1/2(d1)(d2)
d is the length of the diameter
Area of a Rhombus
2 ways
A = bh
OR
A = 1/2(d1)(d2)
d is the length of the diameter
Similar Polygon’s ratio between corresponding sides, perimeters, and areas
Corresponding sides: a/b
Perimeters: a/b
Areas: a²/b²
