With the matrix

Question

A = (0 6
4 12)
I have calculated the inverse of
(-1/2 1/4
1/6 0)

I'm then asked to find the equation of the image f(C) in the unit circle C, in the form of ax^2 +bxy+cy^2=d, where a, b, c and d are integers.
I have currently got;
(40x^2 -36xy +9y^2)/(144) =1

Is this correct or should I not have fractions involved?

Answer 1

For inverse
check multiply

|0 +6| |-1/2 1/4|
|4 12| |+1/6 +0 |
=
1 0
0 1
so right !
I have no idea what the image is about