Question

On a coordinate plane, 2 triangles are shown. The first triangle has points A (negative 2, 1), C (negative 4, 1), and B (negative 3, 4). The second triangle has points A prime (1, negative 2), B prime (4, negative 3), and C prime (1, negative 4).

What is the rule for the reflection?

ry=x(x, y) → (–y, –x)
ry=–x(x, y) → (–y, –x)
ry=x(x, y) → (y, x)
ry=–x(x, y) → (y, x)

Answer 1

R(y=x) = (x, y) → (y, x)

Explanation:

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Answer 2

R(y=x) = (x, y) → (y, x)

Explanation:

The coordinates of A are (-2, 1).

The coordinates of A' are (1, -2).

Clearly, the values have been swapped in accordance with ...

(x, y) → (y, x)

This is the result of a reflection across the line y = x. Hence the rule and its name are ...

R(y=x) = (x, y) → (y, x)