The broken pole forms a RIGHT triangle with the ground
the slanted portion we will cal 'h' (as in 'hypotenuse' )
the vertical portion is 5 - h
and the other leg of the triangle (the ground ) = 3
(5-h)^2 + 3^2 = h^2
h^2 -10h+25+9 = h^2
-10h = -34
h = 3.4 the pole broke 3.4 meters from the top .... AC is thus: 5-3.4 = 1.6 meters