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Point O is the center of the circle. Chord AB has length 32 cm and the distance from the center of the circle to chord AB is 9cm. A What is the length of radius AO (to the nearest tenth)?

Point O is the center of the circle. Chord AB has length 32 cm and the distance from-example-1
User Kellogs
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1 Answer

4 votes

Answer:

The length of radius AO is;


18.4\operatorname{cm}

Step-by-step explanation:

Let C represent the point at which the line from the center intersect the chord AB.

Given;


\begin{gathered} AB=32\operatorname{cm} \\ OC=9\operatorname{cm} \end{gathered}

we can see that the line from the center forms a right angle with the chord AB at point C.

So, the length AC will be half of Chord AB;


\begin{gathered} AC=(AB)/(2) \\ AC=\frac{32\operatorname{cm}}{2} \\ AC=16\operatorname{cm} \end{gathered}

Since AOC form a right angled triangle, we can apply pythagoras theorem to calculate the radius AO;


\begin{gathered} AO^2=OC^2+AC^2 \\ AO=\sqrt[]{OC^2+AC^2} \end{gathered}

substituting the values we have;


\begin{gathered} AO=\sqrt[]{9^2+16^2} \\ AO=\sqrt[]{81+256} \\ AO=18.36\operatorname{cm} \\ AO=18.4\operatorname{cm} \end{gathered}

The length of radius AO is;


18.4\operatorname{cm}

User Johan Leino
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