1.
One way to show that a statement is NOT a good definition is to find a _____.
Correct Answer
D. Counterexample
Explanation
A counterexample is a specific example or case that contradicts or disproves a statement. In this context, if a statement is claimed to be a good definition but a counterexample can be found that does not fit the definition, it demonstrates that the statement is not a good definition. Therefore, a counterexample is a valid way to show that a statement is NOT a good definition.
2.
Rewrite the biconditional as a conditional
statement. Then write its converse and determine if the biconditional
is an accurate definition.An angle is obtuse if and only if its measure is greater than ninety degrees.
Correct Answer
B. No, it is not an accurate definition.
Explanation
it could be a straight angle (a line)
3.
Which biconditional is a good definition?
Correct Answer
C. Two angles are supplementary if and only if they form a linear pair.
4.
Use the Law of Detachment to draw a conclusion.A bisector of a line segment intersects the segment at its midpoint. bisects at D.
Correct Answer
A. D is the midpoint of Segment CE.
Explanation
The Law of Detachment states that if a conditional statement is true and the hypothesis of the conditional statement is true, then the conclusion of the conditional statement is also true. In this case, the given information states that a bisector of a line segment intersects the segment at its midpoint. The statement "D is the midpoint of Segment CE" is a conclusion that can be drawn from this information because it matches the given condition. Therefore, the answer is D is the midpoint of Segment CE.
5.
Which is the Law of Syllogism in symbolic form?
Correct Answer
A. If p → q and q → r are true statements, then p → r is a true statement.
Explanation
The Law of Syllogism in symbolic form states that if p → q and q → r are true statements, then p → r is also a true statement. This means that if the first statement implies the second statement, and the second statement implies the third statement, then the first statement implies the third statement as well.
6.
Select the appropriate property of equality for the statement a = a.
Correct Answer
B. Reflexive Property
Explanation
The reflexive property states that any quantity is equal to itself. In this case, the statement "a = a" shows that the quantity 'a' is equal to itself, which aligns with the reflexive property.
7.
N the figure shown m∠AED = 97. Which statement is false?
Correct Answer
D. # ∠BEC and m∠CED are vertical angles.
Explanation
The statement "# ∠BEC and m∠CED are vertical angles" is false. Vertical angles are formed by two intersecting lines and are always congruent. However, in the figure shown, m∠BEC and m∠CED are not congruent angles, so they cannot be vertical angles.
8.
Name an angle complementary to ∠COD.
Correct Answer
B. ∠BOC
Explanation
An angle complementary to ∠COD is an angle that, when added to ∠COD, will result in a sum of 90 degrees. Among the given options, ∠BOC is the only angle that, when added to ∠COD, will result in a sum of 90 degrees. Therefore, ∠BOC is the correct answer.
9.
If ∠A and ∠B are supplementary angles and m∠A = 4m∠B, find m∠A and m∠B.
10.
Find the value of the variable.
11.
Two angles whose sides are opposite rays are called _____. Two coplanar
angles with a common side, a common vertex, and no common interior
points are called _____.
Correct Answer
B. Vertical angles; adjacent angles
Explanation
Vertical angles are formed by two intersecting lines and are opposite each other. They share a common vertex but do not have any common interior points. Adjacent angles, on the other hand, share a common side and a common vertex, but do not have any common interior points. Therefore, the correct answer is vertical angles; adjacent angles.
12.
Select the appropriate property of equality for the statement. If a = b, then a • c = b • c.
Correct Answer
C. Multiplication Property
Explanation
The correct answer is Multiplication Property because it states that if two quantities are equal (a = b), then multiplying both sides of the equation by the same number (c) will still result in equality (a • c = b • c). This property allows us to perform the same operation on both sides of an equation without changing its truth value.
13.
Use the Law of Detachment to draw a conclusion.I will have room for dessert if and only if I do not finish my dinner. I finished my dinner.
Correct Answer
D. No conclusion possible
Explanation
need the hypothesis to be true: I will have room for dessert
14.
Use the Law of Syllogism to draw a conclusion.If a substance is water, then its molecular structure is H2O. If a substance has molecular structure H2O, then its boiling point at sea level is 100°C.
15.
Supply the missing reason and statement in the following proof.Given: m∠1 = m∠3Prove: m∠AFC = m∠DFB
16.
Which is a counterexample that proves this conditional is false?All prime numbers are odd.
Correct Answer
D. 2
Explanation
The number 2 is a counterexample that proves the conditional "All prime numbers are odd" false because 2 is a prime number but it is not odd.
17.
Supplementary angles are two angles whose measures have sum _____.
Complementary angles are two angles whose measures have sum _____.
18.
Use the Law of Detachment and the Law of Syllogism to draw a conclusion from the given statements.
Franz is taller than Isabel.
Isabel is shorter than Ellen.
Janina is taller than Franz.
Correct Answer
B. Janina is taller than Isabel.
Explanation
Based on the given statements, we can use the Law of Syllogism to conclude that Janina is taller than Isabel. The first statement tells us that Franz is taller than Isabel, and the second statement tells us that Isabel is shorter than Ellen. By applying the Law of Syllogism, we can infer that Franz is taller than Ellen. Finally, since the third statement states that Janina is taller than Franz, we can conclude that Janina is taller than Isabel.
19.
Complete the proof.Given: ∠A and ∠B are right angles.Prove: ∠A ≈ ∠BBy the definition of a. _____ m∠A = 90 and m∠B = 90. By the b. _____ Property m∠A = m∠B or ∠A ≅ ∠B.
Correct Answer
a. right angles
b. substitution
Explanation
By the definition of a right angle, we know that the measure of angle A is 90 degrees and the measure of angle B is also 90 degrees. By the substitution property, we can conclude that the measures of angles A and B are equal, or in other words, angle A is congruent to angle B.
20.
Use the Law of Syllogism to draw a conclusion.If a country's
population is more than 1.033 billion, then it has a higher population
than India. If a country has a higher population than India, then it is
has the highest population in the world.
21.
Find the value of the variables.