a. AC=3 dm=30 cm
AB+BC=17cm+13cm=30cm=> AB+BC=AC=> B€(aparține) (AC)=> A,B,C coliniare
(Pt că AC=30)
b. AB=29cm
AC=42 cm
BC=13 cm
AB+BC=29cm+13cm=42cm=> AB+BC=AC=> B€(AC)=> A,B,C coliniare
c. AB=40 cm
AC=1,5cm
BC=38,5cm
AB+BC=40cm+38,5cm
AB+BC=78,5cm=> AB+BC nu e = AC deci B nu € AC => A, B, C nu sunt coliniare
d. AB=4,8cm
AC=6cm
BC=12 cm
AB+BC= 12cm+4,8cm=16,8cm
=> AB+BC nu e = AC=> B nu €AC=> A,B,C nu sunt coliniare
