<span>Naming of rays
Rays are commonly named in two ways:
By two points.
In the figure at the top of the page, the ray would be called AB because starts at point A and passes through B on it's way to infinity. Recall that points are usually labelled with single upper-case (capital) letters. There is a symbol for this which looks like this: AB This is read as "ray AB". The arrow over the two letters indicates it is a ray, and the arrow direction indicates that A is the point where the ray starts.
By a single letter. (I have not seen this done.)
The ray above would be called simply "q". By convention, this is usually a single lower case (small) letter. This is normally used when the ray does not pass through another labeled point.</span>
12)
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13)
First of all, sorry for not including a picture - I hope I can describe this well enough:
Call the centre of the circle O, the chord AB (touching the circumference at A and B) and the midpoint of AB M. From circle theorems, we know that a radius, passing through the midpoint of a chord, will be perpendicular to it. Therefore we have a right-angled triangle OMA, with the hypotenuse OA forming the radius of length 13in, the line OM being 5in as stated in the question, and the side AM being an unknown.
By Pythagoras' theorem, AM = <span>√(13^2 - 5^2) = 12in (it's a 5,12,13 Triple)
Because M is the midpoint of AB, this value needs to be doubled to get the length of AB as 24in. One inch is 2.54cm (3sf), so the length of the chord is:
24 * 2.54 = 60.96cm, which rounds to 61.0cm (3sf)
I hope this helps
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Answer:
x = 6
Step-by-step explanation:
use alternate angles