Question 845081
<pre><font face = "Tohoma" size = 3 color = "indigo"><b> 
Hi,
1/4x^2+1/4y^2=16
0r
 x^2 + y^2 = 64 
 x^2 + y^2 = 8^2  C(0,0) r = 8
{{{drawing(300,300,   -10,10,-10,10,  arc(0,0,16,16),
 grid(1),
graph( 300, 300, -10,10,-10,10))}}}