## Renee99 3 years ago The figure below shows triangle PQR with a circumscribed circle of radius 7 inches. http://assets.openstudy.com/updates/attachments/505b3fd4e4b0cc122893ea30-renee99-1348157619927-456845882011121142pm1902385864.png Which segment must measure 7 inches? A. segment RO B. segment RQ C. the angle bisectors D. the perpendicular bisectors

1. Renee99

there's also this one: Look at triangle PQR. http://assets.openstudy.com/updates/attachments/505b3fd4e4b0cc122893ea30-renee99-1348157849369-456845882011122801pm596145625.png Segment QX is an angle bisector. Which statement must be true? A. length of segment XP = 6 inches B. length of segment XQ = 4 inches C. measure of angle XQR = measure of angle XQP = 35˚ D. measure of angle QRX = 180˚ – (90˚+ 35˚) = 180˚ – (125˚) = 55˚ I think the answer is A, is that right?

2. Renee99

I don't know the first one, but I think the second one is A

3. abdul_shabeer

Segment QX is an angle bisector. What do you understand by this?

4. Renee99

i cut the triangle in half

5. Renee99

it*

6. abdul_shabeer

It divides the angle into two

7. Renee99

and half of 12 is 6 so that's where I get my answer...

8. abdul_shabeer

It does not divide the side, it only divides the angle.

9. Renee99

ohh okay.

10. abdul_shabeer

In case of an isosceles triangle, it divides the opposite side also.

11. Renee99

well, I know its not C nor B

12. abdul_shabeer

Why not C?

13. Renee99

because the measure of angle XQR is 70 not 35 right

14. Renee99

wait, looking at the wrong problem...

15. Renee99

hold on im mixed up, was looking at the other problems pic... lol

16. Renee99

but yeah, the angle is 70 and not 35 isnt it?

17. abdul_shabeer

Angle PQR is 70

18. Renee99

ohhh, okay, then that would make C the answer

19. abdul_shabeer

Right

20. Renee99

because half of 70 is 35! okay thanks so much! could u maybe help me with the first one now?

21. abdul_shabeer

Which length is the radius for first question?

22. Renee99

well, its says a circumscribed circle of radius 7 inches, which kind of confuses me, but I always thought the radius was the doted line?

23. abdul_shabeer

24. Renee99

okay, so now how do we find the measure that equals 7 inches?

25. abdul_shabeer

Why did you think the dotted line is the radius?

26. Renee99

Idk, I think its a subconscious thing, I just remember that the dotted line should be the radius?

27. Renee99

28. abdul_shabeer

If you want to conclude that OR is radius, then you must prove that O is the centre of the circle.

29. abdul_shabeer

here's where circumcentre comes into play

30. Renee99

okay... so then would that mean that the answer is A, since we're saying it's the radius?

31. abdul_shabeer

Answer is right, but you cannot just conclude that OR is radius. The main question is that you need to prove that OR is radius

32. Renee99

okay, isn't there a formula for that, I don't have my formula sheet with me, but if I remember correctly, isn't something like 3.14(R)^2

33. Renee99

I cant remember the exact formula

34. abdul_shabeer

No need of any formula

35. abdul_shabeer

Do you know what does circumcentre mean?

36. Renee99

where the three perpendicular bisectors meet?

37. abdul_shabeer

And it's also the centre of circle

38. abdul_shabeer

In the picture, two pependicular bisectors meet, which means the third perpendicular bisector would also meet at the same point.

39. abdul_shabeer

by this you can conclude that O is the centre of circle.

40. abdul_shabeer

41. Renee99

gotcha, thanks for ur help! I really really appreciate it!

42. abdul_shabeer

No problem

43. abdul_shabeer

Are you good at chemistry?

44. Renee99

somewhat, im taking chemistry this year...

45. Renee99

I know the basic;s of chemistry pretty well

46. Renee99

basic's*

47. abdul_shabeer

What is hardwater?

48. Renee99

I believe hard water is water that has high mineral content...

49. Renee99

or something like that, not sure, look it up?

50. abdul_shabeer

Ok, thanks

51. Renee99

np :)