+113 For what value of k does the equation x^2+10x+y^2+6y-k=0 represent a circle of radius 6?
+45 I seriously don't understand why so many people like to copy questions with latex...
where do they come from???
+2094 I don't know. Alcumus?
Please write out the question completely... I'll try to help when you do! :D
+310 A circle equation is \((x-h)^2+(y-k)^2=r^2\), where (h, k) is the center and r is the radius.
We complete the square for x and y to get it in circle form.
Add 25 and 9 to both sides to complete the square. \(x^2+10x+25+y^2+6y+9-k=25+9\)
Now we can write the squares. We also k to both sides. \((x+5)^2+(y+3)^2=34+k\)
It's in circle equation now!
Since the radius must be 6, 34+k=36.
k=2
