VOCABULARY
POSTULATES
THEOREMS
CIRCLE FORMULAS
LOGIC & PROOFS
100

What are the two parts of a conditional statement?

Hypothesis and conclusion

100

How many points determine a line?

Two points

100

What is the sum of the angles in any triangle?

180°

100

What is the formula for the circumference of a circle with diameter d?

C=πd

100

A chain of reasoning “If A → B and B → C, then A → C” is called a ________.

Syllogism

200

A statement accepted without proof is called a ________.

Postulate

200

How many noncollinear points determine a plane?

Three noncollinear points

200

The Pythagorean Theorem applies only to what type of triangle?

Right triangle

200

What is the formula for the circumference using radius r?

C=2πr

200

A direct proof begins with known _________.

Premises

300

What do we call a statement that must be proven true?

Theorem

300

A postulate is accepted without _________.

Proof

300

In the Pythagorean Theorem, the longest side of the triangle is called the ________.

Hypotenuse

300

What is the formula for the area of a circle?

A=πr2

300

An indirect proof is also called proof by ________.

Contradiction

400

“If and only if” means the statement is true in how many directions?

Both directions

400

True or false: Postulates can never be used in proofs.

False

400

Which theorem states that a2+b2=c2?

Pythagorean Theorem

400

If a circle has radius 5, what is its area?

25π or 78.5398

400

A diagram that shows relationships between sets or statements is called a(n) ________.

Euler diagram

500

A word whose meaning is agreed upon but not formally defined is called a(n) ________.

Undefined term

500

Which postulate explains why you only need two points to sketch a straight line?

Two Points Determine a Line Postulate

500

Which theorem states that the angles of a triangle add to 180°?

Triangle Angle Sum Theorem

500

If a circle has diameter 12, what is its circumference?

12π or 37.6991

500

The converse of a conditional statement does what?

Reverses the hypothesis and conclusion