"There is no chord of a circle that is longer than its diameter." How do you justify this statement? Class 9

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· Jul 08, 2026 · Reviewed & updated Sep 17, 2026 · 1 min read

"There is no chord of a circle that is longer than its diameter." How do you justify this statement? Class 9

Question 1.

"There is no chord of a circle that is longer than its diameter." How do you justify this statement? Class 9

Solution:

Consider a circle with centre O and radius r.

Let AB be any chord of the circle.

OA = OB = r

Now, in any triangle,

Sum of any two sides > third side

∴ OA + OB > AB

∴ r + r > AB

∴ 2r > AB

But 2r is the diameter of the circle.

∴ No chord is longer than the diameter.