## kcla1996 Group Title Find the distance between the two points. Round to the nearest tenth if necessary. (2, 5) and (–1, –5) one year ago one year ago

1. ash.vasvani Group Title

Make a triangle, Pythagorean theorem.

2. hartnn Group Title

or you could use this : Distance between points (x1,y1) and (x2,y2) is $$\huge d=\sqrt{(x_1-x_2)^2+(y_1-y_2)^2}$$

3. CliffSedge Group Title

Distance formula is derived from Pythagoras' Theorem, I've found it's easier for students to remember the one formula than have to memorize another one.

4. CliffSedge Group Title

|dw:1349496154838:dw|

5. CliffSedge Group Title

It's easy enough to see what the lengths of the legs of the triangle are, then solve for the hypotenuse.

6. kcla1996 Group Title

1?

7. kcla1996 Group Title

Here are the choices: A. 1 B. 109 C. 10.4 D. 3

8. kcla1996 Group Title

9. CliffSedge Group Title

|dw:1349496503466:dw|

10. CliffSedge Group Title

1 doesn't seem very reasonable for points that far apart.

11. kcla1996 Group Title

10.4?

12. CliffSedge Group Title

That seems more reasonable, but how can you be sure? What if it wasn't a multiple choice question and you had to provide an exact value, not just one rounded to the tenths' place?

13. kcla1996 Group Title

oh i just counted how long the triangle's height was on the picture you drew, and i counted 10

14. kcla1996 Group Title

is it right?

15. CliffSedge Group Title

Ah, no. You have to use Pythagorean Theorem to find the hypotenuse of the right triangle. |dw:1349498042456:dw| Or perhaps you would have been better off using the distance formula hart provided..

16. kcla1996 Group Title

ok i'll try it....i'll tell you what i get

17. kcla1996 Group Title

oh wait

18. kcla1996 Group Title

how do i put (2,5) and (-1,-5) in that equation

19. AriPotta Group Title

coordinates are (x,y) so substitute the coordinates' x's and y's

20. kcla1996 Group Title

109?

21. hartnn Group Title

yup, now don't forget to take aquare root.

22. hartnn Group Title

*square

23. kcla1996 Group Title

oh thank you! so it's 10.4 :D

24. hartnn Group Title

welcome :)