Prentice Hall Geometry

See Problem 4.

  1. Proof Given: eh b bar , box drawings double vertical . d c bar , comma . angle b approximately equal to angle d comma

    eh b bar , approximately equal to . d c bar , comma . b c bar , approximately equal to . eh d bar

    Prove: cap delta eh b c approximately equal to cap delta c d eh

    Triangles ABC and CDA share side AC. Sides AB and CD are equal and parallel. Angles B and D are equal. Sides DA and BC are equal.

B Apply

  1. If cap delta d e f approximately equal to cap delta l m n comma  which of the following must be a correct congruence statement? Triangle DEF has short side DF and long side EF. Triangle LMN has short side LN and long side MN.
    1. d e bar , approximately equal to . l n bar
    2. f e bar , approximately equal to . n l bar
    3. angle n approximately equal to , angle f
    4. angle m approximately equal to , angle f
  2. Reasoning Randall says he can use the information in the figure to prove cap delta b c d approximately equal to cap delta d eh b .  Is he correct? Explain.

    Triangles BCD and DAB share side BD. Sides CD and AB are equal and sides BC and DA are equal. Angles CBD and ADB are equal and angles ABD and CDB are equal.

Algebra cap delta eh b c approximately equal to cap delta d e f .  Find the measures of the given angles or the lengths of the given sides.

  1. m angle , eh equals . x plus 10 comma . m angle . d equals 2 x
  2. m angle . b equals 3 , y comma m angle , e equals 6 y , minus 12
  3. b c equals , 3 z plus 2 , comma e f equals , z plus 6
  4. eh c equals , 7 eh plus 5 , comma d f equals , 5 eh plus 9
  5. Think About a Plan cap delta eh b c approximately equal to cap delta d b e .  Find the value of x.

    Triangles ABC and DBE share vertex B. Interior angles at 51 degrees at ABC, 81 degrees at E, and (x + 5) degrees at A.

    • What does it mean for two triangles to be congruent?
    • Which angle measures do you already know?
    • How can you find the missing angle measure in a triangle?

Algebra Find the values of the variables.

  1. Triangles ABC and KLM have right angles at B and L. Angle A is 45 degrees and side AB is 4 inches. Angle M is 3x degrees and side KL is 2t inches.

    cap delta eh b c approximately equal to cap delta k l m

  2. Triangles ACD and ACB share side AC. Angle DAC is 6x degrees and angle BAC is 30 degrees.

    cap delta eh c d approximately equal to cap delta eh c b

  3. Complete in two different ways: cap delta j l m approximately equal to  __?__.

    A triangle has corners J, L and M, and another has corners N, R, and Z. Angles L and R are equal and angles M, J, N, and Z are equal. Sides JM and ZN are equal, and sides ML, LJ, NR, and RZ are equal.

  4. Open-Ended Write a congruence statement for two triangles. List the congruent sides and angles.
  5. Proof Given: eh b bar , up tack , eh d bar , comma , b c bar , up tack , c d bar , comma , eh b bar , approximately equal to , c d bar , comma , eh d bar , approximately equal to , c b bar , comma , eh b bar . double vertical bar , c d bar

    Prove: cap delta eh b d approximately equal to cap delta c d b

    Triangles ABD and CDB share side BD, with right angles at A and C. Sides AB and CD are parallel and equal. Sides AD and BC are equal.


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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