120k views
0 votes
Choose all of the statements that correctly describe the transformation rule. Reflection over x-axis: (x, y) ? (?x, y) Reflection over y-axis: (x, y) ? (x, ?y) Rotation of 90° counter-clockwise about origin: (x, y) ? (?y, x) Rotation of 180° counter-clockwise about origin: (x, y) ? (?x, ?y) Rotation of 270° counter-clockwise about origin: (x, y) ? (y, ?x)

User Radmation
by
5.8k points

2 Answers

3 votes

Answer:Transformations are important subjects in geometry. In this exercise, these are the correct transformation rules:

Explanation:

User Michael Lukin
by
5.1k points
3 votes

Answer:

Transformations are important subjects in geometry. In this exercise, these are the correct transformation rules:

1. Reflection over x-axis:

Consider the point
(x,y), if you reflect this point across the x-axis you should multiply the y-coordinate by -1, so you get:


\boxed{(x,y)\rightarrow(x,-y)}

2. Reflection over y-axis:

Consider the point
(x,y), if you reflect this point across the y-axis you should multiply the x-coordinate by -1, so you get:


\boxed{(x,y)\rightarrow(-x,y)}

3. Rotation of 90° counter-clockwise about origin:

Consider the point
(x,y). To rotate this point by 90° around the origin in counterclockwise direction, you can always swap the x- and y-coordinates and then multiply the new x-coordinate by -1. In a mathematical language this is as follows:


\boxed{(x,y)\rightarrow(-y,x)}

4. Rotation of 180° counter-clockwise about origin:

Consider the point
(x,y). To rotate this point by 180° around the origin, you can flip the sign of both the x- and y-coordinates. In a mathematical language this is as follows:


\boxed{(x,y)\rightarrow(-x,-y)}

5. Rotation of 270° counter-clockwise about origin:

Rotate a point 270° counter-clockwise about origin is the same as rotating the point 90° in clock-wise direction. So the rule is:


\boxed{(x,y)\rightarrow(y,-x)}

User Carter
by
5.8k points