Answer:
x = 3.5
Step-by-step explanation:
Since CD is an angle bisector the following ratios are equal
[tex]\frac{CB}{CA}[/tex] = [tex]\frac{BD}{AD}[/tex], that is
[tex]\frac{6}{5}[/tex] = [tex]\frac{4.2}{x}[/tex] ( cross- multiply )
6x = 21 ( divide both sides by 6 )
x = 3.5
