Réponse :
Explications étape par étape
AB / AM = AC / AN
x / (x + 7 ) = 5 / 14
⇔ 5 ( x + 7 ) = 14x
⇔ 5x + 35 = 14 x
⇔ 9x = 35
⇔ x = 35 / 9
⇔ x ≅ 3,88
CA / CN = BA / BM
x / ( 4 + x ) = 9 / 29
⇔ 9 ( 4 + x ) = 29x
⇔ 36 + 9x = 29x
⇔ 20x = 36
⇔ x = 9/5
⇔ x = 1,8
BA / BN = CA / CM
18 / ( 18 + x ) = 20 / 28
⇔ ( 18 + x ) . 20 = 18 . 28
⇔ 360 + 20 x = 504
⇔ 20x = 144
⇔ x = 36 / 5
⇔ x = 7,2
