Answer:
x = 3
Step-by-step explanation:
Look at the picture.
If ABC is any triangle and AD bisects (cuts in half) the angle BAC, then
[tex]\dfrac{AB}{DB}=\dfrac{AC}{DC}[/tex]
In our triangle we have the proportion:
[tex]\dfrac{AD}{AC}=\dfrac{BD}{BC}[/tex]
We have
AD = 2.25, AC = 3, BC = 4, BD = x.
Substitute:
[tex]\dfrac{2.25}{3}=\dfrac{x}{4}[/tex]
[tex]\dfrac{x}{4}=0.75[/tex] multiply both sides by 4
[tex]\boxed{x=3}[/tex]
