Math
posted by Joshua on .
Hi guys,
In the question "It is given that P (0, 3), Q(7, 5), R(9, 2) and S are vertices of a square. A circle A passes through the points P, Q, R and S. Find the equation of this circle. Hence or otherwise find the equation of circle B which is the image of A under the reflection about y – axis."
Can someone help me with the part hence or otherwise? I've found that the equation of the circle is x^2 + y^2 9x y 6 =0
Thanks =)

Assuming your answer is correct, it can be written
(x  9/2)^2 + (y  1/2)^2 = 106/4
(check my numbers)
The reflection about the y axis would be
(x + 9/2)^2 + (y  1/2)^2 = 106/4 
Hi drwls,
Just wondering, does the word "under" in the question influence the question at all?
Thanks for your reply! =) 
In this mathematics context, "Under the reflection about (an axis)" is the same as saying "after a reflection about (an axis)"
Mathematicions often us the preposition "under" to indicate carrying out an operation. It does not mean "below" in this case. 
Thanks drwls for the good explanation =)

jack has 3/4 of a dollar. Maxwell has 1/10 of a dollar. Do they have more or less than $1.oo in all?