Which rule describes the transformation that is a reflection across the x-axis?

a- (x,y)>(x,-y)

b- >(-x,y)

c_ >(-x,-y)

d- >(y,x)

my answer is a

right on

thank you

A parallelogram is transformed according to the rule (x,y) (x,y) what is another way to state the transformation

You are correct! The rule that describes the transformation of a reflection across the x-axis is (x, y) -> (x, -y), which corresponds to option a.

To understand how to arrive at this answer, let's break down the reflection across the x-axis:

For any point (x, y) in the coordinate plane, reflecting it across the x-axis involves keeping the x-coordinate the same and changing the sign of the y-coordinate.

Therefore, the rule can be written as (x, y) -> (x, -y), which matches option a: (x, y) -> (x, -y).

By applying this rule, each point will be reflected across the x-axis, effectively flipping the shape or object over the x-axis.