Inscribed circle

The circle inscribed in a triangle has a radius 3 cm. Express the area of the triangle using a, b, c.

Result

S = (Correct answer is: 1.5*(a+b+c))

Step-by-step explanation:

$$\begin{gathered} r=3\text{ cm } \\ r=2S\mathrm{/}(a+b+c) \\ S=1.5\cdot (a+b+c)={\displaystyle \frac{3}{2}}=1\frac{1}{2} \end{gathered}$$

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