Herons Formula CBSE Questions & Answers

Herons Formula

This is Mathematics Class 09 Herons Formula CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
The area of the the triangle having sides 1 m, 2 m and 2 m is :
  • A
    \(4\sqrt {15} \;{m^2}\)
  • B
    \({{15} \over 4}{m^2}\)
  • C
    \({{\sqrt {15} } \over 4}{m^2}\)
    Correct
  • D
    \({{\sqrt {15} } \over 2}{m^2}\)
2
The sides of a triangular flower bed are 5 m, 8 m and 11 m. the area of the flower bed is
  • A
    \(\sqrt {300} \;\;{m^2}\)
  • B
    \(4\sqrt {21} \;{m^2}\)
    Correct
  • C
    \(21\sqrt 4 \;\;{m^2}\)
  • D
    \(\sqrt {330} \;\;{m^2}\)
3
The length of the sides of a triangle are 5 cm, 7 cm and 8 cm. Area of the triangle is :
  • A
    \(50\sqrt 3 \;c{m^2}\)
  • B
    \(100\sqrt 3 \;c{m^2}\)
  • C
    300 \(c{m^2}\)
  • D
    \(10\sqrt 3 \;c{m^2}\)
    Correct
4
Area of an equilateral triangle of side 2 cm is :
  • A
    1 \(c{m^2}\)
  • B
    \(\sqrt 3 \;c{m^2}\)
    Correct
  • C
    \(\sqrt 2 \;c{m^2}\)
  • D
    \(\sqrt 5 \;c{m^2}\)
5
The base of a right triangle is 8 cm and hypotenuse is 10 cm. Its area will be :
  • A
    80 \(c{m^2}\)
  • B
    24 \(c{m^2}\)
  • C
    48 \(c{m^2}\)
  • D
    40 \(c{m^2}\)
    Correct
6
An isosceles right triangle has area 8\(c{m^2}\). The length of its hypotenuse is :
  • A
    \(\sqrt {32} \;\;cm\)
    Correct
  • B
    \(\sqrt {16} \;\;cm\)
  • C
    \(\sqrt {24} \;\;cm\)
  • D
    \(\sqrt {48} \;\;cm\)
7
Area of the given triangle is
Question 7 figure 1
  • A
    )30 \(c{m^2}\)
    Correct
  • B
    78 \(c{m^2}\)
  • C
    60 \(c{m^2}\)
  • D
    32.5 \(c{m^2}\)
8
Each equal side of an isosceles triangle is 13 cm and its base is 24 cm Area of the triangle is :
  • A
    60 \(c{m^2}\)
    Correct
  • B
    \(25\sqrt 3 \;c{m^2}\)
  • C
    \(40\sqrt 3 \;c{m^2}\)
  • D
    \(50\sqrt 3 \;c{m^2}\)
9
The sides of a triangle are in ratio 3 : 4 : 5. If the perimeter of the triangle is 84 cm, then area of the triangle is :
  • A
    274 \(c{m^2}\)
  • B
    290 \(c{m^2}\)
  • C
    294 \(c{m^2}\)
    Correct
  • D
    252 \(c{m^2}\)
10
The sides of a triangle are 4 cm, 8 cm and 6 cm. The length of the perpendicular from the opposite vertex to the longest side is :
  • A
    \(4\sqrt {15} \;cm\)
  • B
    \({4 \over 3}\sqrt {15} \;cm\)
  • C
    \(3\sqrt {15} \)cm
  • D
    \({3 \over 4}\sqrt {15} \;cm\)
    Correct
11
Each side of an equilateral triangle is 2 x cm. If \(x\sqrt 3 = \sqrt {48} ,\) then area of the triangle is :
  • A
    16 \(c{m^2}\)
  • B
    \(48\sqrt 3 \;\;c{m^2}\)
  • C
    \(16\sqrt 3 \) \(c{m^2}\)
    Correct
  • D
    \(\sqrt {48} \) \(c{m^2}\)
12
The sides of a triangle are x, y and z. If x + y = 7 m, y + z = 9 m, and z + x = 8 m, then area of the triangle is :
  • A
    5 \(\;{m^2}\)
  • B
    7 \(\;{m^2}\)
  • C
    4 \(\;{m^2}\)
  • D
    6 \(\;{m^2}\)
    Correct
13
If the area of an equilateral triangle is \(16\sqrt 3 \;c{m^2},\) then the perimeter of the triangle is :
  • A
    12 cm
  • B
    48 cm
  • C
    24 cm
    Correct
  • D
    306 cm
14
The base of a right triangle is 8 cm and hypotenuse is 10 cm. Its area will be
  • A
    80 \(\;c{m^2}\)
  • B
    24 \(\;c{m^2}\)
    Correct
  • C
    40 \(\;c{m^2}\)
  • D
    48 \(\;c{m^2}\)
15
The sides of a triangle are 56 cm, 60 cm and 52 cm long. Then the area of the triangle is
  • A
    1322 \(c{m^2}\)
  • B
    1311 \(c{m^2}\)
  • C
    1392 \(c{m^2}\)
  • D
    1344 \(c{m^2}\)
    Correct