Twenty QuestionsReview Game

Chapter 2

Twenty Questions

1 2 3 4 5

6 7 8 9 10

11 12 13 14 15

16 17 18 19 20

1. Name the property that justifies each statement.

AB = AB

reflexive

2. Name the property that justifies each statement.

RS = TU and TU = YP, then RS = YP

transitive

3. Name the property that justifies each statement.

If AB + BC = CD and BC = 10, then AB + 10 = CD.

substitution

4. Name the property that justifies each statement.

If AB + CD = EF + CD, then AB = EF.

Subtraction CD from both sides

5. Determine if a valid conclusion can be reached from the two true statements. If a valid conclusion can be reached, state it and the law you used.

If a shape has four right angles, then it is a rectangle.Quadrilateral ABCD has four right angles.

Detachment, Quadrilateral ABCD is a rectangle.

6. Determine if a valid conclusion can be reached from the two true statements. If a valid conclusion can be reached, state it and the law you used.

If it is January and it is raining, then the roads will freeze.If we do not go to school, then the roads are frozen.

invalid

7. Determine if the third statement follows from the first two statements. If it does, state the law that was used. If it does not, write invalid.

If a shape is a parallelogram, then its opposite sides are parallel.Quadrilateral ABCD has opposite sides parallel.Quadrilateral ABCD is a parallelogram.

Invalid

8. Determine if the third statements follows from the first two statements. If it does, state the law that was used. If it does not, write invalid.

If it is July, then it is humid.If it is humid, then a person is sweating.If it is July, then a person is sweating.

syllogism

9. Write the inverse of the following statement:

If it is Saturday, then Carolyn goes for a long run.

If it is not Saturday, then Carolyn does not go for a long run.

10. Write the converse of the following:

If it is Monday, then Mr. Cole wears a bowtie.

If Mr. Cole is wearing a bowtie, then it is Monday.

11. Translate into symbolic form:

p: Miranda is not wearing a skirt.Q: Mrs. Mitchell is not old.Mrs. Mitchell is not old or Miranda is wearing a skirt.

Q V ~ p

12. Translate into written:

p: Miranda is not wearing a skirt.q: Mrs. Mitchell is not old.

~ q ^ ~ p

Mrs. Mitchell is old and Miranda is wearing a skirt.

13. Determine if the following conjecture is true or false. If it is false, give a counterexample.

Given: Angles 1 and 2 are complementary.Conjecture: Angles 1 and 2 are adjacent.

False, they do not have to be adjacent, just sum to 90.

14.Make a conjecture based on the given information. Draw a figure to illustrate your conjecture.

Given: Angles 1 and 2 form a linear pair.

Example: The sum of the angles is 180

15. Draw a Venn diagram to represent the following:

If you are wearing a jersey today, then you play field hockey.

Wear jersey today inside play field hockey

16. Identify the conclusion:

All right angles measure 90 degrees.

Measure 90 degrees.

17. Write the following in if-then form.

Every square has four congruent sides.

If a shape is a square, then it has four congruent sides.

18. Determine if a valid conclusion can be reached from the two true statements. If a valid conclusion can be reached, state it and the law you used.

All triangles have three sides.ABC is a triangle.

Detachment, ABC has three sides.

19. Determine if a valid conclusion can be reached from the two true statements. If a valid conclusion can be reached, state it and the law you used.

All quadrilaterals have angles that sum to 360.All shapes that have angles that sum to 360 have four sides.

All quadrilaterals have four sides. syllogism

20. Name the property:

If AB = CD, then 2AB = 2CD

Multiplication by 2