Congruence Flashcards
Independent statements
Don’t depend on anything else to prove it is what it is
What triangle congruence cannot be trusted
SSA,ASS,AAA do not guarantee congruency
Dependent statements
Depend on independent statements to prove it is what it is
What happens if a shape is regular
All of it’s sides and interior angles are congruent
Definition of a midpoint
Midpoint will divide one line into two equal parts
Reflexive property
A line is equal to itself
DF is congruent to DF
Addition property of equality
If equal quantities are added to equal quantities, the sums are equal
AB+BC=DC+CB
Substitution
A quantity may be substituted for its equal in an expression
AB+BC=AC
DC+CB=DB
AB+BC=DC+CB-> AC=DB
Segment addition
2 segments are added together to make a longer segment
AB+BC=AC
Vertical angles are congruent
2 intersecting lines form 2 sets of vertical angles which are congruent to each other
Supplements of angles are congruent
Adjacent angles will create 180° therefore if angles are proven congruent by a triangle congruence, then it’s adjacent angles will be equal as well
Compliments of angles are congruent
Adjacent angles will create 90° therefore if angles are proven congruent by a triangle congruence, then it’s adjacent angles will be equal as well
Linear pair
If two angles from a linear pair, then they are supplementary
Base angle theory for isosceles triangles
If 2 sides of a triangle are congruent, then their base angles are congruent as well
Base angle converse for isosceles triangles
If two sides of a triangle are congruent, then their opposite angles are congruent as well
SSS TRIANGLE CONGRUENCE
If 3 sides of 1 triangle are congruent to 3 sides of another triangle then the triangles are congruent
SAS TRIANGLE CONGRUENCE
If 2 sides and the included angle of 1 triangle are congruent to the sir responding parts of another triangle, then the triangles are congruent
ASA TRIANGLE CONGRUENCE
If 2 angles and the included side of one triangle are congruent to the corresponding parts of another triangle, then the triangles are congruent
AAS triangle congruence
If 2 angles and the non included side of 1 triangle are congruent to the corresponding parts of another triangle, then the triangles are congruent
CPCTC
Corresponding Parts of Congruent Triangles are Congruent, usually comes after proof that two triangles are congruent
Hypotenuse leg congruence for right triangles
Hypotenuse and 1 leg of right triangle are congruent to the corresponding parts of another right triangle, the two right triangles are congruent
Leg leg congruence for right triangles
If the leg and leg of one right triangle are congruent to the corresponding parts of another right triangle, then the two right triangles are congruent
Leg acute angle congruence for right triangles
If 1 leg and an acute angle of a right triangle are congruent to one leg and the corresponding acute angle of another right triangle, then the triangles are congruent
Hypotenuse acute angle congruence right triangle
Hypotenuse and leg of right triangle are congruent to hypotenuse and corresponding leg of another right triangle then the triangles are congruent
Corresponding angles
If 2 parallel lines are cut by a transversal, then the pairs of corresponding angles are congruent
Corresponding angles converse
If 2 lines are cut by a transversal and the corresponding angles are congruent the lines are parallel
Alternate interior angles are congruent
If 2 parallel lines are cut by a transversal, then the alternate interior angles are congruent
Alternate exterior angles are congruent
If two parallel lines are cut by a transversal, then the alternate exterior angles are congruent
Alternate interior angles converse
If 2 lines are cut by a transversal and the alternate interior angles are congruent, then the lines are parallel
Alternate exterior angles converse
If 2 lines are cut by a transversal and the alternate exterior angles are congruent, then the lines are parallel
Transitive property
Bridge
AB is congruent to CD
CD is congruent to EF
Therefore AB is congruent to EF
What does SSA produce ?
Ambiguity not reliable ! Don’t use