URGENT DM A RENDRE POUR DEMAIN

on appelle x la longueur CF

BM//CD

thales

AB/AC = AM/AF = BM/CF

3/6 = BM/x
3x = 6BM
BM = 3x/6 = x/2

FD = 6-x

on reponds à la question par l'équation :

x/2 = 6-x
[tex] \frac{x}{2} = 6-x[/tex]
12-2x = x
-2x-x = -12
3x = 12
x = 4

CF = 4cm