Question

Va rog am nevoie de problema 4.
Am nevoie de punctul a. Va rog mult.Dau coroana

Answer 1

Răspuns:

Explicație pas cu pas:

20.  MN║BC ⇒

AM/AB=AN/AC=MN/BC

AS =5+10 =15 cm

AM/AB=MN/BC

5/10=MN/14

MN=5*14/10 =7 cm

AM/AB=AN/AC

5/15 =3/3+NC

5(3+NC)=3*15

15+5NC =45

5NC=45-15 =30

NC =6 cm

21.

MN║AB⇒

CN/BC=CM/AC=MN/AB

MN/AB=CN/BC

20/30=12/12+BN

20(12+BN)=30*12

240+20BN=480

20BN=480-240=240

BN =12 cm

MN/AB=MC/AC

20/30=MC/MC+7

20(MC+7)=30MC

20MC+140 =30MC

30MC-20MC =140

10MC=140

MC=14 cm