1. (x , y) → (kx , ky) = Dilation ; similar image
2. (x , y) → (y , -x) = Rotation 90 counterclockwise ; congruent
3. (x , y) → (-x , y) = Reflection over y-axis ; congruent
4. (x , y) → (-x , -y) = Rotation 180 ; congruent
5. (x , y) → (x, -y) = Reflection over x-axis ; congruent
6. (x , y) → (-y , x) = Rotation 90 clockwise ; congruent
7. (x , y) → (x + a , y + b) = Translation ; congruent
Hope this helps :)
1. But you are actually counting how many lines across a circle can have, then it is infinite.
