side a = 12

side b = 18

side c = 20

median of side b = (sqrt( ( 2 * 12 * 12 ) + ( 2 * 20 * 20 ) - ( 18 * 18 ) )) / 2

median of side b = 13.8203

where,

a = side a

b = side b

c = side c

P = perimeter

K = area

height = height

m = median

t = angle bisector

R = circumscribed circle radius

r = inscribed circle radius

s = semi perimeter

ta = angle bisector of side a

tb = angle bisector of side b

tc = angle bisector of side c

ma = median of side a

mb = median of side b

mc = median of side c

ha = altitude of side a

hb = altitude of side b

hc = altitude of side c

A = angle A

B = angle B

C = angle C

base = base