Question

HELP!! Not hard, just confusing.. 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)

Answer 1

1st one : A′(-3, 3), B′(-1, 1), C′(-2, 3)

Explanation:

below

Answer 2

Correct answer is A.

The reflection across the x-axis changes the sign of the y-coordinate of the point, while the x-coordinate remains the same.

A(-3, 1)
`\rightarrow` A''(-3, -1)
B(-1, 3)
`\rightarrow` B''(-1, -3)
C(-2, 1)
`\rightarrow` C''(-2, -1)

Translation 4 units up increases the y-coordinate for 4, while the x-coordinate remains the same.

A''(-3, -1)
`\rightarrow` A'(-3, 3)
B''(-1, -3)
`\rightarrow` B'(-1, 1)
C''(-2, -1)
`\rightarrow` C'(-2, 3)