Question

Complete both transformations below. Then enter the final coordinates of the figure.

A (-4,0)

B

A" ([?], []) C" ([], [])

C (-3,-3)

1) Reflect across y-axis 2) < -5,2>​

Answer 1

• A"(-1, 2)
• B"(-5, 1)
• C"(-2, -1)

Explanation:

You want points A(-4, 0), B(0, -1) and C(-3, -3) reflected across the y-axis and translated left 5 and up 2.

Transformation

The reflection across the y-axis changes the sign of the x-coordinate:

(x, y) ⇒ (-x, y)

The translation adds the translation vector to the reflected coordinates.

(x, y) ⇒ (x -5, y +2) . . . . . . translation (by itself)

Then the result of both transformations is ...

(x, y) ⇒ (-x -5, y +2)

For a number of points, this arithmetic is conveniently accomplished by a calculator. The result is ...

• A"(-1, 2)
• B"(-5, 1)
• C"(-2, -1)