Answer:
Y = -2
Explanation:
A reflection will produce a mirror image of the shape. Both shapes will be equal distance from the line of reflection and perpendicular to it.
To find it, connect Q and Q' with a line segment. Do the same to all corresponding vertices. The line of reflection will be perpendicular to these segments. This means it is a horizontal line through the y-axis and of the form y=b.
To find the y-coordinate b, subtract the y-values of U and U' then divide by 2.
U is (1,2) and U' is (1,-6) so (2--6)/2 = 8/2=4. The line of reflection is 4 units below U and 4 units above U'. This is -2. The line of reflection is y = -2.