## anonymous 4 years ago Coordinate geometry State the perimeter of the triangle in simplest radical form.

1. anonymous

A side: A to B is 6, B to C is -4 to 4, C to A: 6

2. anonymous

i'm confused 'cause the answer is 8 + 4√13... how?

3. Mertsj

Is it a right triangle?

4. anonymous

yes, it is

5. anonymous

no, it's an equilateral triagnle

6. Mertsj

So let me see if I have this right

7. Mertsj

No. Just a minute. What do you mean A to B is 6?

8. Mertsj

Side AB is 6 units long?

9. Mertsj

A/B= 6?

10. Mertsj

Can you draw a picture?

11. anonymous

here. |dw:1328386455510:dw|

12. Mertsj

|dw:1328386617260:dw|

13. anonymous

yup

14. Mertsj

in order to find the perimeter you have to find the lengths of all the sides and add them together. BC=8

15. anonymous

ohh, okay.

16. Mertsj

$AC=AB=\sqrt{6^2+2^2}=\sqrt{40}=2\sqrt{10}$

17. Mertsj

So the total of the three sides is $8+2\sqrt{10}+2\sqrt{10}=8+4\sqrt{10}$

18. anonymous

ooohh

19. anonymous

thank you!

20. Mertsj

No wait. I made a mistake

21. Mertsj

$AB=AC=\sqrt{6^2+4^2}=\sqrt{52}=2\sqrt{13}$

22. anonymous

huh?

23. Mertsj

So total perimeter is the same except change the 10 to a 13

24. anonymous

how did you get 2√13?

25. Mertsj

$\sqrt{52}=\sqrt{4\times13}=2\sqrt{13}$

26. anonymous

ohh... i see it now. Thank you!

27. Mertsj

yw.