Prentice Hall Geometry
  1. Writing You and a friend compete in a scavenger hunt at a museum. The two of you walk from the Picasso exhibit to the Native American gallery along the dashed red line. When he sees that another team is ahead of you, your friend says, “They must have cut through the courtyard.” Explain what your friend means.

    A museum is a rectangle with the Native American Gallery at the top left corner and Picasso Exhibit at the bottom right corner. A pathway extends between the two corners in the rectangular courtyard within the museum.

  2. Error Analysis Your family drives across Kansas on Interstate 70. A sign reads, “Wichita 90 mi, Topeka 110 mi.” Your little brother says, “I didn't know that it was only 20 miles from Wichita to Topeka.” Explain why the distance between the two cities does not have to be 20 mi.

Reasoning Determine which segment is shortest in each diagram.

  1. Quadrilateral PQSR has interior angle P measuring 30 degrees with sides PQ and PR equal. A segment from Q meets R at a right angle, with angle SQR measuring 40 degrees.
  2. Quadrilateral ABCD has interior angle A measuring 30 degrees and diagonal BD, with angle CDB measuring 110 degrees, angle CBD 32 degrees, and angle ABD 114 degrees.
  3. Quadrilateral WXZ has a segment from W meeting side XZ at Y, with angle X 48 degrees, angle Z 40 degrees, angle XWY 47 degrees, and angle WYZ 95 degrees.
  4. Developing Proof Fill in the blanks for a proof of Theorem 5-10: If two sides of a triangle are not congruent, then the larger angle lies opposite the longer side.

    Given: cap delta t o y comma  with y o greater than y t

    Prove: a. modified question mark with under bar below , greater than  b. modified question mark with under bar below

    Mark P on y o bar  so that y p bar , approximately equal to . y t bar , .  Draw t p bar , .

    Triangle TOY has a segment from T meeting side OY at P, forming triangles TPO and TPY. In triangle TPY, angle 1 is at P, angle 2 is at T, and sides PY and TY are equal. Triangle TPO has angle 3 at O and angle 4 at T.

    Statements Reasons
    1) y p bar , approximately equal to , y t bar 1) Ruler Postulate
    2) m angle , 1 equals , m angle 2 2) c. modified question mark with under bar below
    3) m angle o t y equals m angle , 4 plus , m angle 2 3) d. modified question mark with under bar below
    4) m angle o t y greater than m angle 2 4) e. modified question mark with under bar below
    5) m angle o t y greater than m angle 1 5) f. modified question mark with under bar below
    6) m angle , 1 greater than , m angle 3 6) g. modified question mark with under bar below
    7) m angle o t y greater than m angle 3 7) h. modified question mark with under bar below
  5. Proof Prove this corollary to Theorem 5-11: The perpendicular segment from a point to a line is the shortest segment from the point to the line.

    Triangle PTA has a right angle at T.

    Given: p t bar , up tack , t eh bar

    Prove: p eh greater than p t

C Challenge

  1. Probability A student has two straws. One is 6 cm long and the other is 9 cm long. She picks a third straw at random from a group of four straws whose lengths are 3 cm, 5 cm, 11 cm, and 15 cm. What is the probability that the straw she picks will allow her to form a triangle? Justify your answer.

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Table of Contents

Prentice Hall Geometry Chapter 1 Tools of Geometry Chapter 2 Reasoning and Proof Chapter 3 Parallel and Perpendicular Lines Chapter 4 Congruent Triangles Chapter 5 Relationships Within Triangles Chapter 6 Polygons and Quadrilaterals Chapter 7 Similarity Chapter 8 Right Triangles and Trigonometry Chapter 9 Transformations Chapter 10 Area Chapter 11 Surface Area and Volume Chapter 12 Circles Skills Handbook Reference Visual Glossary Selected Answers Index Acknowledgments