... im C cho BC = 3cm 14 A 40 50 cm 20 160 30 3cm C 180 170 170 700 10 10 20 160 180 V on thng AC, ta c tam giỏc ABC 150 B 70 110 60 13 14 80 V xBy = 70 y V thờm tam giỏc ABC cú: AB = 2cm, BC = 3cm, ... BNG NHAU TH HAI CA TAM GIC CNH - GểC CNH (c.g.c) V tam giỏc bit hai cnh v gúc xen gia: = 70 Bi toỏn: V tam giỏc ABC bit AB = 2cm, BC = 3cm, B Giai x 110 120 70 100 90 100 80 60 120 Trờn tia Bx ... nghim rng c tam giỏc ABC bng tam giỏc ABC hay khụng? AC = AC = 3cm x BC = BC = 3cm Nờn ABC = ABC (c.c.c) x 120 70 100 90 100 80 70 120 50 40 150 30 20 160 2cm 700 180 10 10 170 160 3cm 20 B 3c...