Mathematics

Problem

A triangle has side lengths

7\,\text{cm}

8\,\text{cm}

and

9\,\text{cm}

. What is its area correct to one decimal place? a)

28.0\,\text{cm}^2

19.0\,\text{cm}^2

26.8\,\text{cm}^2

30.0\,\text{cm}^2