Two triangles and each have perimeter

MATHEMATICS · Subjective · CBSE · Mathematics · Heron's Formula · Heron's Formula

Problem

Two triangles

P

and

Q

each have perimeter

42\,\text{cm}

. The sides of

P

are

18\,\text{cm}

12\,\text{cm}

and

12\,\text{cm}

, while the sides of

Q

are

17\,\text{cm}

15\,\text{cm}

and

10\,\text{cm}

. (a) For each triangle, calculate the semi-perimeter. (b) Using an appropriate formula, find the area of each triangle correct to one decimal place. (c) State which triangle has the greater area and justify your answer by quoting the numerical results obtained in part (b).

Related theory

Heron's Formula
Area of Triangles
Mensuration
Triangle area and perimeter

Browse the problem library