## OpenSessame 2 years ago Question about coordinate geometry!

1. OpenSessame

Prove using coordinate geometry: If a point is on the perpendicular bisector of a segment, then it is equidistant from the endpoints of the segment. You are given a line segment (AB) and a perpendicular line segment (CD).

2. OpenSessame

@BangkokGarrett Can you help?

3. BangkokGarrett

I don't know how to draw on here. Answering geometry questions without being able to draw like this is hard on this website for me. Sorry!

4. OpenSessame

Theres a draw button...

5. BangkokGarrett

|dw:1376019437389:dw|

6. OpenSessame

LOL

7. BangkokGarrett

Sorry. I still don't know really how to answer your original question. It seems kinda common sense that the statement is true.

8. OpenSessame

i KNOW. Can you see what i wrote and see if its right?

9. BangkokGarrett

I don't see what you wrote?!?

10. OpenSessame

In the triangle ADC and BDC, AD and BD are congruent because D is the midpoint of the segment AB. Also the side DC is common in both the triangles. This mean that angle CDA and angle CDB are both 90 degrees meaning they are congruent. This means the triangles are congruent because of the postulate Side-Angle-Side. So since the triangles are congruent, the distance from the two endpoints have to be equal.

11. BangkokGarrett

CDA and CDB are both 90 by the definition of "perpendicular" in the given. Otherwise sounds great!

12. OpenSessame

It does, because in doing test makeup and they counted it all wrong...

13. BangkokGarrett

Geometry teachers can get all uptight about the exact way you state theorems and such. This type of thing annoys me if you ask me. I'd give you 100% because you obviously understand the concepts.

14. OpenSessame

Thanks still have a 92 in geo so im okay!

15. BangkokGarrett

Good luck!

16. OpenSessame

thanks!