esli ABCD pryamougolnik i BD=12
togda storony budu ravny : AB=DC i AD=BC
AB"2 + BC"2 = AC"2
BC"2 + CD"2 = BD"2 (12"2)
otsyuda sleduet, 4to AC = BD = 12
esli nachertit etot pryamougolnik s etimi pryamymi (AC i BD), ottuda my naidem (po pifagoru) 4to storony AB,BC,CD i AD budut ravny = 6*koren2
prowad treugolnika ravna :
(1/2)*AB*BC = (1/2) 6*koren2*6*koren2 = 36
esli ABCD pryamougolnik i BD=12
togda storony budu ravny : AB=DC i AD=BC
AB"2 + BC"2 = AC"2
BC"2 + CD"2 = BD"2 (12"2)
otsyuda sleduet, 4to AC = BD = 12
esli nachertit etot pryamougolnik s etimi pryamymi (AC i BD), ottuda my naidem (po pifagoru) 4to storony AB,BC,CD i AD budut ravny = 6*koren2
prowad treugolnika ravna :
(1/2)*AB*BC = (1/2) 6*koren2*6*koren2 = 36