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Calculate the length of a chord which is at a perpendicular distance of5 cm from the centre of a circle of radius 13 cm. |
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Answer» ⇒ Final Answer: 28 cm ⇒ Given: Perpendicular distance from the chord to the centre of the circle = 5 cm Radius of the circle = 13 cm Please REFER the attachment for pictorial representation. ⇒ To Find: The length of the chord. ⇒ Solution: In the diagram: AD = 13 cm DC = 5 cm It is given that: the perpendicular distance from the chord to the centre of the earth is 5 cm. This means that, ΔACD is right angled. Now, applying the Pythagoras THEOREM, Altitude² + Base² = Hypotenuse² AD² + DC² = AC² 13² + 5² = AC² 169 + 25 = AC² 196 = AC² AC = √196 AC = 14 cm As AC is the half of the complete chord AB, the measure the complete chord = 2 x 14 = 28 cm Hence the required answer is 28 cm. Knowledge Bytes:→ IMPORTANT terms used in the answer: ✳ Chord A chord is a line SEGMENT that connects two points in the boundary of the circle. The longest chord in a circle is the diameter. ✳ Radius The radius is the short line segment that connects the center of the circle to any point in the boundary of the circle. A diameter is 2 x radius. The measure of a radius of a circle is always the same. |
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