# Urgent Help Needed

• August 8th 2009, 05:46 PM
itsMoeyy
Urgent Help Needed
Hi I need help for this question

I need the solution, working out and the explanation for the steps.

Thanks :)

http://img15.imageshack.us/img15/7071/diagramv.png

Triangle ACB and Triangle APO are equilateral

(i) Explain why Angle BAO = Angle PAC
(ii) Prove Triangle AOB is congruent to Triangle APC
(iii) Hence. Prove OP=CP
• August 8th 2009, 07:38 PM
eXist
Is this in 3 dimensional space? or is this on a flat surface? To me it looks like that's a pyramid :D
• August 8th 2009, 07:40 PM
artvandalay11
Quote:

Originally Posted by itsMoeyy
Hi I need help for this question

I need the solution, working out and the explanation for the steps.

Thanks :)

http://img15.imageshack.us/img15/7071/diagramv.png

Triangle ACB and Triangle APO are equilateral

(i) Explain why Angle BAO = Angle PAC
(ii) Prove Triangle AOB is congruent to Triangle APC
(iii) Hence. Prove OR=CP

$\angle BAC=60$ since the triangle is equilateral

$\angle BAC= \angle BAO +\angle OAC=60$

$\angle OAP=60$ since the triangle is equilateral

$\angle OAP=\angle PAC +\angle OAC=60$

Therefore $\angle BAO+\angle OAC=\angle PAC+\angle OAC$

And so $\angle BAO=\angle PAC$

I think you should be able to see part II, you'll get 2 sides are the same because of the equilateral triangle, and since we just showed the angles are the same, you only need one more piece

For part III, there is no R in the diagram
• August 8th 2009, 08:07 PM
itsMoeyy
Oh wow. thanks!

Srry it was actually ment to be

OP=CP

Thanks

Oh and its a flat surface and not a pyramid lol.