Which of the following cannot be the sides of a triangle
a. 3 cm, 4 cm, 5 cm
b. 2 cm, 4 cm, 6 cm
c. 2.5 cm, 3.5 cm, 4.5 cm
d. 2.3 cm, 6.4 cm, 5.2 cm
Solution:
We have to determine which of the given options cannot be the sides of a triangle.
We know that the sum of the lengths of any two sides of a triangle is always greater than the length of the third side.
(i) considering 3 cm, 4 cm, 5 cm
Let the two sides be 3cm and 4cm
Let the third side be 5 cm
Now, sum of two sides = 3 + 4 = 7 cm
So, 7 > 5
Therefore, option a can be the sides of a triangle.
(ii) considering 2 cm, 4 cm, 6 cm
Let the two sides be 2cm and 4cm
Let the third side be 6 cm
Now, sum of two sides = 2 + 4 = 6 cm
So, 6 = 6
Therefore, option b cannot be the sides of a triangle.
(iii) considering 2.5 cm, 3.5 cm, 4.5 cm
Let the two sides be 2.5 cm and 3.5 cm
Let the third side be 4.5 cm
Now, sum of two sides = 2.5 + 3.5 = 6 cm
So, 6 > 4.5
Therefore, option c can be the sides of a triangle.
(iv) considering 2.3 cm, 6.4 cm, 5.2 cm
Let the two sides be 2.3 cm and 6.4 cm
Let the third side be 5.2 cm
Now, sum of two sides = 2.3 + 6.4 = 8.7 cm
So, 8.7 > 5.2
Therefore, option d can be the sides of a triangle.
✦ Try This: Can 3 cm, 5 cm, 7 cm be the sides of a triangle. Justify your answer
☛ Also Check: NCERT Solutions for Class 7 Maths Chapter 6
NCERT Exemplar Class 7 Maths Chapter 6 Sample Problem 3
Which of the following cannot be the sides of a triangle? a. 3 cm, 4 cm, 5 cm, b. 2 cm, 4 cm, 6 cm, c. 2.5 cm, 3.5 cm, 4.5 cm, d. 2.3 cm, 6.4 cm, 5.2 cm
Summary:
2 cm, 4 cm, 6 cm cannot be the sides of a triangle
☛ Related Questions:
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