Geometry set 1

Biconditional

an angle is a right angle, if and only if it has a measure of 90°

Contrapositive

if AB + BC does not = AC , then B is not between A and AC.

conditional statement

if B is between A and C, then AB + BC = AC.

inverse

if B is not between A and C, the AB + BC does not = AC.

Midpoint thereom

if M is the midpoint of AB, then AM=1/2 AB, MB=1/2 AB

Law of Detachment

if p→q is a true conditional statement and p is true, then q is true.

Law of syllogism

if p→q, then p→r .

Distance Formula

√(x₂-x₁)²+(y₂-y₁)²

Mid-point Formula

(x₁+x₂)÷2, (y₁+y₂)÷2

Vertical Angles

Opposite ∠'s are ≅

Definition of Angle Bisector

Ray that splits an ∠ into 2 ≅ ∠'s

Definition of Supplementary angles

180°

Definition of Linear Pair

2 ∠'s who's sides are opposite rays + sum = 180°

Definition of complementary angles

90°

converse

If AB + BC = AC, then B is between A and C.

Segment Addition Postulate

If B is between A and C, then AB+BC=AC

Definition of Midpoint

If B is the midpoint of AC then AB and AC are ≅ (an ∠ or segment broken into 2 equal parts)

Angle Addition Postulate

If D is in the interior of ∠ABC, then ∠ABD + ∠DBC = ∠ABC