A)
100%-1%=99%=0.99
485/0.99=489.9
489.9 is the amount of payment to be credited
B)
1,201−489.9=711.1 is the balance outstanding
Part A:
An isometric transformation is a type of transformation where the original shape and size of the pre-image is not altered in the image.
To show that the translation was an isometric transformation, we show that the distance between any two points in the pre-image is equal to the distance between the corresponding points in the image.
Consuder, line AB, the distance between point A and point B is given by:

The distance between point A' and point B' in the image is given by:

Similarly checking other points of the pre-image against the corresponding points of the image shows that the size of the pre-image is preserved in the image.
Part 2:
The translation that maps the triangle ABC onto its image are:
Triangle ABC was shifted 4 units to the right.
Triangle ABC was shifted 4 units up.
25.02-24=1.02
1.02/24=.0425
So the sales tax rate is 4.25%