Remark
The intersecting chord theorem states that when 2 chords intersect, the product of the parts of one chord = the product of the 2 parts of the other chord.
In this case ML * LE = IL * LS
Givens
ML = x; LE = 12; IL = 9; LS = 4
Substitute and Solve
12x = 9*4
12x = 36 Divide by 12
x = 36/12
x = 3 Answer <<<<<
