Angle bisector theorem: CD/DB=AC/AB Replacing the known values: 3.4/2.6=AC/4.9 Solving dor AC. Multiplying both sides of the equation by 4.9 4.9(3.4/2.6)=4.9(AC/4.9) (4.9*3.4)/2.6=AC 16.66/2.6=AC AC=16.66/2.6 AC=6.407692308 Rounded to one decimal place: AC=6.4