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Class IX Math

Subjective question for Heron's formula

1.   Find the area of a triangle whose sides are 12 cm, 6 cm and 15 cm.

2.   Find the area of a triangle whose sides are 4.5 cm and 10 cm and perimeter 10.5 cm.

3.   A park in the shape of a quadrilateral ABCD has C = 90°. AB = 18 m, BC = 24 m, CD = 10 m and AD = 16 m. How much area does it occupy?

4.   Find the area of a triangle with base =20cm and height are 10 cm.

5.   Find the area of a triangle having perimeter 32cm. One side of its side is equal to 11cm and difference of the other two is 5cm.

6.   Perimeter of the rhombus is 100 m and its diagonal is 40m. Find the area of rhombus.

7.   Two parallel sides of a trapezium are 60 cm and 77 cm and other sides are 25 cm and 26 cm. Find the area of trapezium.

8.   The perimeter of a triangular field is 135 cm and its sides are in the ratio 25 : 17 : 12. Find its area.

9.   The perimeter of a square is (4x+20)cm. What will be the length of its diagonal?

10.   If area of the hexagon is 24√3cm², find its perimeter

is 3.2 cm.