Urgent SVP Niveau 4ème. Exo 5&6

Exercice 5:

Tu appliques le théorème deThalès:

PR/PT = PQ/PS = RQ/TS

PR/PT = 4/QS = 3/6

Donc:

 4/QS = 3/6

QS= (4x6) / 3 = 8cm

Exercice 6:

Pareil:

RS/RU = RT/RV = TS/UV

1,5/RU = 3/RV = 1,8/3

Donc:

1,5/RU = 1,8/3

RU= (1,5 x 3) / 1,8 = 2,5

3/RV = 1,8 /3

RV = (3x3) / 1,8 = 5

VT = RV - RT

VT = 5 - 3 = 2

SU = RU - RS

SU = 2,5 - 1,5 = 1