Eric Nicholas K's answer to jeno's Secondary 4 A Maths Singapore question.

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Eric Nicholas K
Eric Nicholas K's answer
3324 answers (Tutor Details)
1st
Given answer for (iii) is clearly incorrect.
Eric Nicholas K
Eric Nicholas K
6 months ago
The radius formed by (5, 8) and (12, 8) is a vertical line.

So, the chord must be horizontal with a fixed value of y = 12.

So the points of intersection are (a, 12) and (b, 12). We proceed to use Pythagoras Theorem to find the horizontal distance from (12, 8) to the circle.