Reflections on X-Y Axis

Reflect the point over the y-axis. What is the coordinate of its image?

• (-3,3)

• (3,3)

• (-3,-3)

• (3,-3)

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

If you reflect point (-2,7) over the y-axis, what is its image point?

• (2,7)

• (2,-7)

• (-2,-7)

• (7,-2)

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

If you reflect point (-2,7) over the x-axis, what is its image point?

• (2,7)

• (2,-7)

• (-2,-7)

• (7,-2)

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

If a point remains unchanged after a reflection, then it lies on...

• the line of symmetry

• itself

• the origin

• point (5,6)

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

If a figure is reflected over a line of symmetry, then its image is congruent to it. True or False?

• True

• False

Tags

CCSS.4.G.A.3

What axis is the image reflected over?

• X-axis

• Y-axis

Answer explanation

Think of your axis of reflection as a book spine: If you "turn the page" to move your figure from preimage to image, where would the page have been attached?

In this case, the x-axis.

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

Reflections over the x-axis change the ____-__________.

• y-coordinate

• x-coordinate

Answer explanation

If you compare the points in the visual example, you can see that the x-values are the same but the sign of the y-value was changed.

Therefore, reflecting over the x-axis changes the y-coordinate.

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

What would be the coordinates of point K if it was reflected over the x-axis?

• (-5, -2)

• (-5, 2)

• (5, -2)

Answer explanation

Think of your axis of reflection as a book spine: If you "turn the page" to transform your figure, with the page attached to the x-axis, where does point K' end up?

(-5,2) on the other side of the x-axis

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

Identify the transformation from ABC to A'B'C'.

• 90^o clockwise rotation

• 90^o counter clockwise rotation

• Reflection across the y-axis

• Reflection across the x-axis

Answer explanation

The image appears to be flipped from the preimage, which indicates a reflection.

The figure would need to be flipped/reflected across the x-axis to be oriented the way it is. Think of it like a page turned from preimage to image, with the page "attached" at the x-axis.

Tags

CCSS.8.G.A.3

CCSS.HSG.CO.A.5

Describe a sequence of transformations that maps figure A onto figure B.

• A translation 4 units right followed by a reflection across the x-axis

• A reflection across the x-axis followed by a reflection across the y-axis

• A reflection across the y-axis followed by a translation 6 units down

• A 90° counterclockwise rotation about the Origin followed by a reflection across the y-axis

Answer explanation

One step that would take figure A to figure B is a 180 degree rotation. This is the same as a reflection over the x-axis followed by a reflection across the y-axis.

Tags

CCSS.8.G.A.3