Download grade-9-Herons-Formula-us

ID : us-9-Herons-Formula [1]
Grade 9
Herons Formula
For more such worksheets visit www.edugain.com
Answer the questions
(1)
Find the area of the figure below. Also find the altitude to the base of the triangle.
(All measurements are in centimeters)
(2)
A rhombus has all its internal angles equal. If one of the diagonals is 9 cm, find the length of other
diagonal and the area of the rhombus.
(3)
The area of a triangle with sides 26 cm, 25 cm and 3 cm is :
(4)
The sides of a quadrilateral, taken in order are 13 cm, 10 cm, 12 cm and 5 cm respectively. The angle
contained by the last two sides is a right angle. Find the area of the quadrilateral.
(5)
Find the percentage increase in the area of a triangle if each side is increased to 8 times.
(6)
The perimeter of an isosceles triangle is 162 cm and its unequal side is 80 cm. Find the area of the
triangle.
(7)
The two adjacent sides of a parallelogram are 4 cm and 13 cm. If one of its diagonals is 15 cm, find the
area of the triangle.
Copyright 2017 www.edugain.com
Personal use only. Commercial use is strictly prohibited.
ID : us-9-Herons-Formula [2]
(8)
If in the figure below AB = 15 cm, BC=20 cm and CA = 7 cm, find the area of the rectangle BDCE.
(9)
A field in the shape of trapezium has its parallel sides as 30 m and 27 m while the non parallel sides are
25 m and 26 m. Find the amount of money farmer has to pay if the cost of sowing the seeds per m2
area is $50.
(10) The area of an equilateral triangle with a side of 8 cm is :
(11) The perimeter of a triangular field is 90 meters and the ratio of the sides is 13:12:5. Find the area of the
field.
(12) Zachary makes the kite using two pieces of paper. 1st piece of paper is cut in the shape of square
where one diagonal is of the length 26 cm. At one of the vertex of this square a second piece of paper
is attached which is of the shape of an equilateral triangle of length to give the shape of a kite. The
length of the sides of triangle is a, such that a2 = 8√3. Find the area of this kite.
(13) Find the area of the parallelogram ABCD and the length of the altitude DE in the figure below:
Copyright 2017 www.edugain.com
Personal use only. Commercial use is strictly prohibited.
ID : us-9-Herons-Formula [3]
Choose correct answer(s) from the given choices
(14) In Heron's formula,
, S is equal to:
a. a + b + c
b.
c. Half of perimeter of the triangle
d.
axbxc
2
a+b+c
abc
(15) The perimeter of a triangular field is 400 m and the ratio of the sides is 17:15:8. Which of the following
is the area of the field in sq m :
a. 4000
b. 6000
c. 180000
d. 4200
© 2017 Edugain (www.edugain.com).
All Rights Reserved
Copyright 2017 www.edugain.com
Many more such worksheets can be
generated at www.edugain.com
Personal use only. Commercial use is strictly prohibited.
ID : us-9-Herons-Formula [4]
Answers
(1)
Area : 126 cm 2
Altitude : 19.38 cm
(2)
9 cm, 40.5 cm 2
(3)
36 cm 2
(4)
Area : 90 cm 2
(5)
6400 %
(6)
360 cm2
(7)
48 cm 2
(8)
Area : 192 cm 2
(9)
$34200
(10)
cm 2
(11) 270
(12) 344 cm2
(13) Area : 84 cm 2
Altitude : 12 cm
(14) c. Half of perimeter of the triangle
(15) b. 6000
Copyright 2017 www.edugain.com
Personal use only. Commercial use is strictly prohibited.