GeometryCreating Sensory Images

Reflections

Your Task with Your PartnerCollect a poster paper, ruler, protractor, a

thumb tack, and marker.

Hang the poster paper on the wall. Using your marker, divide it vertically down the middle.

On the left side of the poster, draw a large, scalene triangle. Label its vertices A, B, and C.

Face the board when finished.

Rotate, 1 Poster to the RightFold the paper on the vertical line.

Using the thumb tack, mark points A, B, and C so that the blank side of the paper is marked.

Unfold the paper. Use your marker to mark the holes on the blank side, and label them A’, B’, and C’, corresponding to the original side of the poster.

Use a straight edge to draw triangle A’B’C’.

Face the front when finished.

Rotate, 1 Poster to the RightUse a ruler to draw segment AA’.

Measure the perpendicular distance in cm from A to the fold. Label the distance.

Measure the perpendicular distance in cm from A’ to the fold. Label the distance.

What do you notice?

Face the front when finished.

Rotate 1 Poster to the RightMeasure the angles formed by the fold the the

segment AA’. Label the measures.

What do you notice?

Face the front when finished.

Rotate 1 Poster to the RightUse a ruler to draw segment BB’.

Measure the perpendicular distance in cm from B to the fold. Label the distance.

Measure the perpendicular distance in cm from B’ to the fold. Label the distance.

What do you notice?

Face the front when finished.

Rotate 1 Poster to the RightMeasure the angles formed by the fold the the

segment BB’. Label the measures.

What do you notice?

Face the front when finished.

Rotate 1 Poster to the RightUse a ruler to draw segment CC’.

Measure the perpendicular distance in cm from C to the fold. Label the distance.

Measure the perpendicular distance in cm from C’ to the fold. Label the distance.

What do you notice?

Face the front when finished.

Rotate 1 Poster to the RightMeasure the angles formed by the fold the the

segment CC’. Label the measures.

What do you notice?

Based upon what you’ve seen, make an inference. How is the reflection line related to the segment joining a point and its image? Write your inference at the bottom of the poster.

Return your supplies. Each of you pick up a problem sheet & piece of graph paper and return to your seats.

With your partner….Complete the problem I assign to you on the

graph paper. Be ready to explain to the class how using creating a sensory image helped you to answer the question.

Exit Slip Individually complete the exit slip and hand it

to me as you leave today.