9514 1404 393
Answer:
(x, y) ⇒ (y+1, 7-x) . . . rotation 90° CW about (4, 3)
or
(x, y) ⇒ (y+1, x+1) . . . glide reflection across y=x; and translation (1, 1)
Step-by-step explanation:
The figure is apparently rotated 90° clockwise. This can be accomplished a couple of ways: (1) rotation 90° CW about some center; (2) reflection across the line y=x. Because of the symmetry of the figure, we cannot tell which of these is used.
Rotation
The center of rotation can be found by looking at the perpendicular bisectors of the segments joining a vertex and its image. One such segment has endpoints (1, 6) and (7, 6), so is a horizontal line with midpoint (4, 6). The perpendicular bisector of that is x=4.
Another segment joining a point with its image has endpoints (5, 6) and (7, 2). Its midpoint is (6, 4), and the slope of the bisector through that point is 1/2. It intersects the line x=4 at (4, 3), the center of rotation.
Rotation 90° CW about the origin is the transformation (x, y) ⇒ (y, -x), so rotation of (x, y) 90° about the point (4, 3) will be the transformation ...
(x, y) ⇒ ((y -3) +4, (-(x -4) +3) = (y +1, 7 -x)
The transformation A to B is rotation 90° CW about (4, 3):
(x, y) ⇒ (y +1, 7 -x).
__
Reflection
Simple reflection across the line y=x is the transformation (x, y) ⇒ (y, x). Applying that transformation, we see that an additional translation of 1 unit right and one unit up is required. The complete transformation is a "glide reflection", a reflection followed by a translation.
The transformation A to B is a glide reflection across the line y=x with a translation up 1 and right 1:
(x, y) ⇒ (y +1, x +1).
