Question

The perimeter of $△ABC$ is $36cm$ and its in-radius is $8cm$. Then the area of the triangle is

• A. $144c{m}^2$
• B. $124c{m}^2$
• C. $164c{m}^2$
• D. $104c{m}^2$

Answer 1

Answer: (A)

In radius $(r)=\frac{\Delta }{S}$
$\Delta =(r\cdot s),\Delta \to$ Area, $S\to$ Semi-perimeter
$\Rightarrow \Delta =8\times \frac{36}{2}=144c{m}^2$