Geometry easy

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Geometry easy

by jacket882 » Tue Apr 07, 2009 2:37 am
O is the center of the circle.

What is Angle PRQ ?


- The solution is telling me:
Angle POQ is 70deg. Because POQ is a central angle and PRQ is an inscribed angle, the value of PRQ is half the value of POQ. Therefore PRQ = 35deg.

Now I don't get this. The way i did it:
PQR = 90. Therefore 180-90-60 = 30

Any help appreciated.
Attachments
diag.jpg
diagram
Source: — Problem Solving |

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by moutar » Tue Apr 07, 2009 3:34 am
The diagram cannot be true.

PO = QO as both are radii of the circle.
This means that POQ is isoceles and therefore PQO and POQ should be the same. i.e. POQ = 50 degrees

However, as there are 180 degrees in a triangle POQ = 70 degrees.

There must be a mistake somewhere.

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by jacket882 » Tue Apr 07, 2009 3:39 am
you're right

there's a mistake I hadn't noticed that :(

that's the diagram I was given (not OG)