• geometry, the semiperimeter of a polygon is half its perimeter. Although it has such a simple derivation from the perimeter, the semiperimeter appears frequently...
    6 KB (890 words) - 18:19, 18 April 2024
  • Thumbnail for Heron's formula
    ⁠ ⁠ c . {\displaystyle c.} ⁠ Letting ⁠ s {\displaystyle s} ⁠ be the semiperimeter of the triangle, s = 1 2 ( a + b + c ) , {\displaystyle s={\tfrac {1}{2}}(a+b+c)...
    19 KB (3,515 words) - 14:30, 21 November 2024
  • Thumbnail for Right triangle
    {\displaystyle \triangle ABC} with sides a ≤ b < c {\displaystyle a\leq b<c} , semiperimeter s = 1 2 ( a + b + c ) {\textstyle s={\tfrac {1}{2}}(a+b+c)} , area T...
    18 KB (2,954 words) - 15:04, 9 November 2024
  • − d ) {\displaystyle K={\sqrt {(s-a)(s-b)(s-c)(s-d)}}} where s, the semiperimeter, is defined to be s = a + b + c + d 2 . {\displaystyle s={\frac {a+b+c+d}{2}}...
    7 KB (1,334 words) - 19:16, 21 October 2024
  • Thumbnail for Incircle and excircles
    = 1 2 ( a + b + c ) {\displaystyle s={\tfrac {1}{2}}(a+b+c)} is the semiperimeter. The tangency points of the incircle divide the sides into segments...
    34 KB (5,685 words) - 23:39, 16 November 2024
  • perimeter into two equal lengths, this common length being called the semiperimeter of the triangle. The three splitters of a triangle all intersect each...
    11 KB (1,302 words) - 19:39, 25 September 2024
  • Thumbnail for Trapezoid
    ( a + b + c + d ) {\displaystyle s={\tfrac {1}{2}}(a+b+c+d)} is the semiperimeter of the trapezoid. (This formula is similar to Brahmagupta's formula...
    25 KB (3,089 words) - 20:46, 14 November 2024
  • The parameters in a triangle inequality can be the side lengths, the semiperimeter, the angle measures, the values of trigonometric functions of those...
    44 KB (9,338 words) - 12:23, 20 November 2024
  • Thumbnail for Hexagon
    (orig. 1960). Gutierrez, Antonio, "Hexagon, Inscribed Circle, Tangent, Semiperimeter", [1] Archived 2012-05-11 at the Wayback Machine, Accessed 2012-04-17...
    31 KB (2,798 words) - 17:28, 18 November 2024
  • Thumbnail for Cyclic quadrilateral
    d ) {\displaystyle K={\sqrt {(s-a)(s-b)(s-c)(s-d)}}\,} where s, the semiperimeter, is s = ⁠1/2⁠(a + b + c + d). This is a corollary of Bretschneider's...
    31 KB (4,109 words) - 22:54, 14 November 2024
  • Thumbnail for Acute and obtuse triangles
    inequality holding for an obtuse triangle. For an acute triangle with semiperimeter s,: p.115, #2874  s − r > 2 R , {\displaystyle s-r>2R,} and the reverse...
    13 KB (2,153 words) - 09:46, 10 September 2024
  • Thumbnail for Rhombus
    q: K = p ⋅ q 2 , {\displaystyle K={\frac {p\cdot q}{2}},} or as the semiperimeter times the radius of the circle inscribed in the rhombus (inradius):...
    16 KB (1,719 words) - 14:08, 4 November 2024
  • Thumbnail for Altitude (triangle)
    vertex at the right angle. For any triangle with sides a, b, c and semiperimeter s = 1 2 ( a + b + c ) , {\displaystyle s={\tfrac {1}{2}}(a+b+c),} the...
    9 KB (1,321 words) - 03:22, 21 October 2024
  • Thumbnail for Quadrilateral
    where the sides in sequence are a, b, c, d, where s is the semiperimeter, and A and C are two (in fact, any two) opposite angles. This reduces...
    49 KB (6,981 words) - 20:20, 14 November 2024
  • coordinate system Pole Real axis Secant line Circular sector or "sector" Semiperimeter Symmetry Shape Pattern Crystal system Frieze group Isometry Lattice...
    13 KB (910 words) - 13:17, 13 September 2024
  • Thumbnail for Integer triangle
    + c ) {\textstyle 2{\sqrt {bcs(s-a)}}{\big /}(b+c)} where s is the semiperimeter (and likewise for the other angles' bisectors). Any altitude dropped...
    40 KB (7,223 words) - 21:36, 11 October 2024
  • Thumbnail for Triangle inequality
    b,c)<a+b+c} and thus that the longest side length is less than the semiperimeter. A mathematically equivalent formulation is that the area of a triangle...
    34 KB (5,175 words) - 02:40, 21 October 2024
  • Thumbnail for Antiprism
    , R ( z ) {\displaystyle R(z),R(z)} and l 1 {\displaystyle l_{1}} (semiperimeter R ( z ) + l 1 ( z ) / 2 {\displaystyle R(z)+l_{1}(z)/2} ) plus n {\displaystyle...
    18 KB (2,326 words) - 22:08, 4 September 2024
  • s = 1 2 ( a + b + c ) {\textstyle s={\tfrac {1}{2}}(a+b+c)} is the semiperimeter, or half of the triangle's perimeter. Three other equivalent ways of...
    20 KB (3,530 words) - 10:58, 11 November 2024
  • Thumbnail for Pythagorean triple
    radius of the outer Soddy circle of any right triangle is equal to its semiperimeter. The outer Soddy center is located at D, where ACBD is a rectangle,...
    81 KB (11,397 words) - 18:27, 19 October 2024
  • Thumbnail for Incenter
    line segment from the orthocenter to the circumcenter as e, and the semiperimeter as s, the following inequalities hold: d s < d u < d v < 1 3 ; {\displaystyle...
    15 KB (2,225 words) - 14:35, 16 October 2024
  • In the earliest usages, the Greek letter π was used to denote the semiperimeter (semiperipheria in Latin) of a circle and was combined in ratios with...
    148 KB (17,584 words) - 14:55, 11 November 2024
  • Nagel point intersection of lines from each vertex to the corresponding semiperimeter point X(9) Mittenpunkt symmedian point of the triangle formed by the...
    6 KB (346 words) - 04:10, 16 October 2024
  • + c {\displaystyle d={\frac {2{\sqrt {bcs(s-a)}}}{b+c}}} where the semiperimeter s = a + b + c 2 . {\displaystyle s={\tfrac {a+b+c}{2}}.} The side of...
    6 KB (927 words) - 15:12, 7 April 2023
  • Thumbnail for Trigonometric functions
    {A-B}{2}}}{\tan {\frac {A+B}{2}}}}={\frac {a-b}{a+b}}} . If s is the triangle's semiperimeter, (a + b + c)/2, and r is the radius of the triangle's incircle, then...
    77 KB (10,624 words) - 09:02, 16 November 2024
  • Thumbnail for Triangle
    = 1 2 ( a + b + c ) {\displaystyle s={\tfrac {1}{2}}(a+b+c)} be the semiperimeter, T = s ( s − a ) ( s − b ) ( s − c ) . {\displaystyle T={\sqrt {s(s-a)(s-b)(s-c)}}...
    54 KB (6,397 words) - 11:19, 28 October 2024
  • Thumbnail for Concyclic points
    supplementary. A cyclic quadrilateral with successive sides a, b, c, d and semiperimeter s = (a + b + c + d) / 2 has its circumradius given by R = 1 4 ( a b...
    19 KB (2,505 words) - 05:28, 2 November 2024
  • Thumbnail for Midpoint
    the given triangle. The perimeter of the medial triangle equals the semiperimeter (half the perimeter) of the original triangle, and its area is one quarter...
    11 KB (1,414 words) - 11:53, 11 September 2024
  • Thumbnail for Archimedes
    \textstyle k={\sqrt {s(s-a)(s-b)(s-c)}}} , where s {\displaystyle s} is the semiperimeter – was known to Archimedes several centuries before Heron lived. Arabic...
    88 KB (9,821 words) - 16:56, 20 November 2024
  • Thumbnail for Isosceles triangle
    with very sharp angles, because of the near-cancellation between the semiperimeter and side length in those triangles. If the apex angle ( θ ) {\displaystyle...
    37 KB (4,106 words) - 06:40, 19 September 2024