Answer: The required match is given by
A' (1, 1)
B' (2, -1)
C' (3, 0)
D' (2, 1).
Step-by-step explanation: Given that the vertices of polygon ABCD are at A(1, 1), B(2, 3), C(3, 2), and D(2, 1).
ABCD is reflected across the x-axis and translated 2 units up to form polygon A′B′C′D′.
We are to match the vertices of polygon ABCD to its co-ordinates.
We know that
if a point (x, y) is reflected across X-axis, hen the sign before the y co-ordinate changes. Also, if there is an additional translation of 2 units up, then the required transformation will be
(x, y) ⇒ (x, -y + 2).
So, after getting reflected across the X-axis, the co-ordinates of the vertices of ABCD will change as follows :
A(1, 1) ⇒ A'(1, -1+2) = A'(1, 1)
B(2, 3) ⇒ B'(2, -3+2) = B'(2, -1)
C(3, 2) ⇒ C'(3, -2+2) = C'(3, 0)
and
D(2, 1) ⇒ D'(2, -1+2) = D'(2, 1).
Thus, the required match is given by
A' (1, 1)
B' (2, -1)
C' (3, 0)
D' (2, 1).