Unit 2: Logic - Quiz 3: Proof Formats

Match the following items. 1. division 2x + x + 4 = -17 2. subtraction 3x + 4 = -17 3. combine like terms 3x = -21 4. given x = -7

4. 2x + x + 4 = -17 3. 3x + 4 = -17 2. 3x = -21 1. x = -7

In a proof the figure should fit the hypothesis. Never Always Sometimes

Always

The conclusion of a statement is the "then" part. Never Always Sometimes

Always

The hypothesis of a statement is the "if" part. Never Always Sometimes

Always

Which of the following statements has the same truth value as the statement, "If it is Friday, then Bruce has beans for supper." ? If Bruce does not have beans for supper, then it is not Friday. If Bruce has beans for supper, then it is Friday. If it is not Friday, then Bruce does not have beans for supper.

If Bruce does not have beans for supper, then it is not Friday.

Make a deduction from the two given statements. 1.) All cows have tails. 2.) Jersey is a cow. Jersey has a tail. Animals that have tails are cows. All cows are named Jersey.

Jersey has a tail.

A proof should have more steps in the reason column than steps in the statement column. Sometimes Always Never

Never

In the plan of a proof, you should use the plan that was used on previous theorems. Sometimes Always Never

Sometimes

Using the two given statements, is the conclusion true or false ? 1.) Three noncollinear points determine a plane. 2.) Points S, O, N are noncollinear. Conclusion: The points S, O, N form a plane. True or False

True

Make a deduction from the two given statements. 1.) All right angles are equal. 2.) ∠1 and ∠2 are right angles. ∠1 equals ∠2 ∠1 does not equal ∠2 ∠1 is less than ∠2

∠1 equals ∠2