gwd math 30-28

colorsofthewin

Q28:

In the rectangular coordinate system, points (4, 0) and (– 4, 0) both lie on circle C.  What is the maximum possible value of the radius of C ?

 

 

A.        2

B.        4

C.        8

D.     16

E.      There is no finite maximum value.

这一题我有一点不明白，哪位可以给我解释一下。谢了。

sweatfly

E. The two points on the circle are not enough to decide on the radius.

littlegirl

两点的距离可以是任意一根玄与圆的交点。

colorsofthewin

thanks  a  lot ~~~~~~~~~~~~~