Aquarium Feeding Template Trials

Test what happens to angles when feeding-card templates move.

Template trials

An aquarium uses angle-shaped markers on its fish-tank feeding cards. Use a protractor and tracing paper to test the moves. Compare the smaller angle between the rays unless told otherwise.

Trace this marker for the morning feeding card. Slide your tracing to another place on the page without turning it. Measure the angle on your moved tracing.

What is the angle measure after the slide? °

Trace this afternoon feeding marker. Rotate the tracing 90° counterclockwise about its vertex. Which diagram matches the rotated tracing? Keep the vertex in the same place when comparing.

A. B. C. D.

The evening feeding marker is shown below. Trace it, then flip the tracing across the horizontal line through its vertex. Which statement describes the result?

A. The slanted ray points down-right, and the angle measures 135°.B. The slanted ray points up-left, and the angle measures 135°.C. The slanted ray points up-left, and the angle measures 45°.D. The slanted ray points down-right, and the angle measures 45°.

Which actions provide a valid experimental comparison of an original marker and its image? Select all that apply.

Feeding-card layout tests

The connected points in each diagram form an angle, not a triangle. Trace or measure each diagram to check the corresponding angles.

A marker on one tank's feeding card has vertex B. Its image is translated 3 units left and 4 units up. First measure ∠ABC, then slide a tracing to check the image.

What is the measure of the image angle? °

This marker is rotated 180° about the origin. Trace the angle and turn your tracing to test the move. Which statement correctly compares the angles?

A. The original is 90°, and the image is 90°.B. The original is 45°, and the image is 135°.C. The original is 45°, and the image is 45°.D. The original is 45°, and the image is 225°.

To make a feeding card for the opposite side of a tank, reflect this marker across the y-axis. Flip a tracing to check the image of ∠HJK.

What is the measure of the reflected angle? °

A keeper checks the reflected marker in question 7. Which observation is the strongest evidence that the reflection preserved its angle measure?

A. The image has the same number of labeled points.B. The flipped tracing aligns with both rays at the image vertex.C. The image fits within the same coordinate grid.D. The image vertex is on the other side of the y-axis.

Care-team evidence

Use the experiments to evaluate feeding-card designs. Moves apply to the whole marker without stretching or bending it.

A keeper is checking a marker that separates two feeding times. Which test record is consistent with the stated move?

Marker Test Records
Record	Move	Before	After
Morning	Rotation	82°	98°
Midday	Reflection	124°	56°
Evening	Translation	106°	106°
Night	Rotation	39°	129°

A. The evening record is consistent.B. The midday record is consistent.C. The morning record is consistent.D. The night record is consistent.

10.

A feeding-card marker measures 117°. To reuse it on three tank cards, a keeper first rotates it 30° clockwise, then reflects it, then translates it 8 cm. What is the difference between the final angle measure and the original angle measure?

Difference: °

11.

A tank's feeding-card marker measures 68°. A replacement must be made from that marker using only rotations, reflections, and translations. Which replacement could meet this requirement?

A. A marker measuring 136° and pointing up could qualify.B. A marker measuring 68° and pointing left could qualify.C. A marker measuring 112° and pointing right could qualify.D. A marker measuring 34° and pointing down could qualify.

12.

The care team wants evidence for all three kinds of moves, using both acute and obtuse markers. They have already tested an acute marker with a translation and an obtuse marker with a rotation. Which additional trials are needed to test every combination? Select all that apply.

13.

Luis traces a feeding-card marker, slides the tracing, and correctly aligns the two vertices. He turns the tracing until one pair of rays overlaps, but the other pair does not. He concludes that translations change angle measure. Explain why his test does not support that conclusion. Describe what he should check or redo.