## haleym96 Group Title Find the center and radius of a circle that has a diameter with endpoints (-9, -6) and (-1,0). Show work. a) center (4,3); radius 5 b) center (8,6); radius 10 c) center (-5,-3); radius 5 d) center (-10,-6); radius 10 one year ago one year ago

1. CalebBeavers Group Title

Center would be the midpoint between those two points, and the radius would be the distance between them divided by 2

2. haleym96 Group Title

So I do the midpoint formula using the two points to find the center?

3. Hero Group Title

Graph paper would work great for this problem

4. CalebBeavers Group Title

Yep, use the midpoint formula

5. CalebBeavers Group Title

What do you get?

6. haleym96 Group Title

(-5,-3)

7. CalebBeavers Group Title

8. haleym96 Group Title

I know its suppose to be 5, but I didn't get it.

9. CalebBeavers Group Title

Do you know the distance formula?

10. haleym96 Group Title

Wait, I think I know why..

11. haleym96 Group Title

I still didn't get it. Isn't it d=$\sqrt{(x2-x1)^{2}+(y2-y1)^{2}}$

12. CalebBeavers Group Title

Yeah thats it. Plug in your coordinates $D=\sqrt{(-1+9)^2+(0+6)^2}$

13. CalebBeavers Group Title

youll get d=sqrt{100} d=10 but remember thats the diameter, radius is diameter divided by 2. 10/2=5

14. haleym96 Group Title

Oh, I got it now. I just added wrong. Thanks!

15. CalebBeavers Group Title

You're welcome