Chapter 12 – Heron’s Formula

1. The perimeter of a rhombus is 20 cm. One of its diagonals is 8 cm. Then area of the rhombus is

2. If the height of a parallelogram having 500 $cm^{2}$ as the area is 20 cm, then its base is of length

3. The area of quadrilateral PQRS, in which PQ = 7 cm, QR = 6 cm, RS = 12 cm, PS = 15 cm and PR = 9 cm:​

4. The perimeter of a rhombus is 146 cm. One of its diagonals is 55 cm. The length of the other diagonal and area of the rhombus are​

5. Length of perpendicular drawn on smallest side of scalene triangle is

6. The area of a right angled triangle if the radius of its circumcircle is 3 cm and altitude drawn to the hypotenuse is 2 cm.

7. The edges of a triangular board are 6 cm, 8 cm and 10 cm. The cost of painting it at the rate of 70 paise per $cm^{2}$ is

8. The lengths of a triangle are 6 cm, 8 cm and 10 cm. Then the length of perpendicular from the opposite vertex to the side whose length is 8cm is:

9. The area of an equilateral triangle having side length equal to $\frac { \sqrt { 3 } }{ 4 }$ cm is:

10. The base of an isosceles triangle is 10 cm and one of its equal sides is 13 cm. The area of the triangle is

11. The area of an equilateral triangle of side 6 cm is​

12. Length of perpendicular drawn on longest side of a scale △ is

13. A square sheet whose perimeter is 32 cm is painted at the rate of Rs. 5 per m2. The cost of painting is:​

14. The area of a triangle whose sides are 12 cm, 16 cm and 20 cm is

15. Each side of an equilateral triangle measures 10 cm. Then the area of the triangle is

16. The length of the sides of a triangle are 5 cm, 7 cm and 8 cm. Area of the triangle is :

17. The area of a triangle with base 8 cm and height 10 cm is

18. Find the length of each side of an equilateral triangle having area of 9 root 3 cm square

19. Area of triangle is equal to:

20. If the perimeter of a equilateral triangle is 180 cm. Then its area will be:

21. The sides of a triangle are 122 m, 22 m and 120 m respectively. The area of the triangle is:

22. The area of triangle with given two sides 18cm and 10cm respectively and perimeter equal to 42 cm is:

23. The sides of a triangle are in the ratio 12 : 17 : 25 and its perimeter is 540cm. The area is:

24. The equal sides of isosceles triangle are 12 cm and perimeter is 30 cm. The area of this triangle is:

25. A quadrilateral whose sides are 3cm, 4cm, 4cm, 5cm and one of the diagonal is equal to 5cm as per the below figure. The area of the quadrilateral is:

26. The area of an equilateral triangle having side length equal to $\sqrt{\frac{3}{4}}$ cm is:

27. The sides of a parallelogram are 100 m each and length of the longest diagonal is 160m. The area of parallelogram is:

28. The sides of a triangle are in the ratio of 3 : 5 : 7 and its perimeter is 300 cm. Its area will be: