MCQ
In a $\triangle\text{ABC},$ it is given that AD is the internal bisector of $\angle\text{A}.$ If AB = 10cm, AC = 14cm and BC = 6cm, then CD = ?
- A4.8cm
- ✓3.5cm
- C7cm
- D10.5cm
✓
Answer
Correct option: B.
3.5cm
since AD is the bisector of $\angle\text{A},$
by the angle bisector theorem,
$\frac{10}{14}=\frac{6-\text{x}}{\text{x}}$
$\Rightarrow10\text{x}=84-14\text{x}$
$\Rightarrow24\text{x}=84$
$\Rightarrow\text{x}=3.5$
So, CD = 3.5cm.
by the angle bisector theorem,
$\frac{10}{14}=\frac{6-\text{x}}{\text{x}}$
$\Rightarrow10\text{x}=84-14\text{x}$
$\Rightarrow24\text{x}=84$
$\Rightarrow\text{x}=3.5$
So, CD = 3.5cm.
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