Area Formulas!Chapter 11

 

Triangles:

Area of any triangle

 

  • A = ½ bh         where b = base and h = height

 

  •      where s = semiperimeter,  with side lengths a, b, and c

 

Equilateral Triangle

  • A= ½ (ap)(per)    where ap = apothem and per = perimeter

 

Right Triangle

 

  • A=1/2( L1)(L2)      where L1 is the length of one leg and L2 is the length of the other leg

 

Similar Triangles

 

Quadrilaterals

Rectangle

  • A = bh     where b = base and h = height
  •  where s = semiperimeter,  with side lengths a, b, c, and d

 

Square

  • A = s2       where s = length of a side
  • A = bh
  •     where s = semiperimeter,  with side lengths a, b, c, and d
  • A= ½ (ap)(per)    where ap = apothem and per = perimeter
  • A = ½ (D1) (D2)       where D1 = one diagonal's length and D2 = the other diagonal's length

Parallelogram

  • A = bh     where b = base and h = height

 

Trapezoid

  • A = Mh     where M = median and h = height
  • A = ½ h(b1 + b2)      where b1 = one base    and   b2= the other base    and h = height

 

Isosceles Trapezoid

  •     where s = semiperimeter,  with side lengths a, b, c, and d

 

Kite

  • A = ½ (D1) (D2)       where D1 = one diagonal's length and D2 = the other diagonal's length

 

Rhombus

  • A = bh     where b = base and h = height
  • A = ½ (D1) (D2)       where D1 = one diagonal's length and D2 = the other diagonal's length

 

Inscribed Quadrilaterals

  •    where s = semiperimeter,  with side lengths a, b, c, and d

 

Regular polygons

  • A= ½ (ap)(per)    where ap = apothem and per = perimeter

 

Regular Hexagon

  • A= ½ (ap)(per)    where ap = apothem and per = perimeter

Circles

  • A = pr2    where r = radius

Sector of a circle

Segments of a circle

  • A = Asector - Atriangle

 

Similar figures