part 3. Find the coordinates of the vertices of the triangle after a reflection across the y-axis and then across the line y= 2.
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Answer:
c. S'(3, 1), T'(1, -1), U'(0, 1)
Step-by-step explanation:
Reflection across the y-axis negates the x-coordinate, so is equivalent to the transformation ...
(x, y) ⇒ (-x, y)
Reflection across the horizontal line y=c is equivalent to the transformation ...
(x, y) ⇒ (x, 2c-y)
So, the combined reflections are equivalent to the transformation ...
(x, y) ⇒ (-x, 4 -y)
Then we have ...
S(-3, 3) ⇒ S'(-(-3), 4-3) = S'(3, 1)
T(-1, 5) ⇒ T'(-(-1), 4-5) = T'(1, -1)
U(0, 3) ⇒ U'(-(0), 4-3) = U'(0, 1) . . . . matches choice C