Answer:
R(x, y) = (x, -y)
Step-by-step explanation:
When we have a reflection across some line, the distance between the original point and the reflected point to the line is invariant.
For a reflection around the x-axis, the x-value is invariant, then the only value that can change is the y-value.
So if we have a point like (4, 7)
Which is at a distance of 7 units to the x-axis, the only other point that is also at a distance of 7 units to the x-axis that has the same x-value is (4, -7)
Here we already can see the rule.
If we have a point (x, y), the reflection across the x-axis gives us the point (x. -y)
Then we can write this reflection as a function in the next way:
R(x, y) = (x, -y)
This means that if the input is the point (x, y), the output is the point (x, -y)
