Areas - Plane Mensuration Flashcards
(23 cards)
Area of a Square
A= ?
A = a²
Area of a Triangle
A= ?
A= ½ bh
Area of a Rectangle
A = ?
A= bh
Area of a Parallelogram
A= ?
A=bh
Area of an equilateral triangle
A= ?
√3
A= ——— a²
4
Area of a Scalene Triangle
A= ?
A= √ s (s-a)(s-b)(s-c)
Area of a Pentagon
A=?
A= ¼ √ 5(5+2√5) x a²
Area of Hexagon
A=?
3√3
A= ——— a²
2
Area of heptagon
A=?
7 180
A = —— a² cot ( ——— )
4 7
Area of Octagon
A=?
A = 2 (1+√2) a²
Area of Nonagon
A= ?
9
A = —— a² cot 20°
4
Area of Decagon
A= ?
5
A = —— a² √ 5 + 2√5
2
Area of Hendecagon
A =?
11 180
A= —— a² cot (———)
4 11
Area of Dodecagon
A=?
A= 3 a² (2 + √3)
Area of a Rhombus
A = ?
D1 + d2
A = ——————
2
Diagonal of a Rectangle
D= √ a² + b²
Side of a Rhombus
1
S = —— √ d1² + d2²
2
Area of Trapezium
1
A= —— h (a + b)
2
Area of a Circle
A = π r²
Area of a Semi-circle
1
A = —— π r²
2
Area of Sector of a Circle
∅
A = (———) x 2π r²
360 °
Area of the segment of a Circle (sector)
1
A = —— r² ∅
2
Area of Rectangular Parallelepiped
Total A = 2 (ab + bc + ac)
