Question

ΔABC is reflected across the x-axis and then translated 4 units up to create ΔA′B′C′. What are the coordinates of the vertices of ΔA′B′C′ ?

A′(-3, 3), B′(-1, 1), C′(-2, 3)

A′(3, -3), B′(1, -1), C′(2, -3)

A′(3, -5), B′(1, -7), C′(3, -5)

A′(-3, 3), B′(-1, 1), C′(-2, -3)
http://cdn.ple.platoweb.com/PCAP-ASSETS-PROD/7bc301f7cc0c4b418a7e7694b9e6420f

Answer 1

Reflection about the x-axis:
sx: (x,y)->(x,-y)
That means that a point (4,5) will be transformed to (4,-5)
Translation of 4 units up:
\(t_{(0,4)}: (x,y)->(x,y+4)\)
That means that a point (4,-5) will be transformed to (4, -1)
Example:
If a point (-1,2) is subject to the above transformations, we have:
sx(-1,2)->(-1,-2)
\(t_{(0,4)}: (x,y)->(x,y+4)\)(-1,-2)->(-1,2)