Summary Matric IEB geometry

complementaryangles sum of 90

supplementary angles sum of 180
Vertapp Ls are equal

Anglesaround a point 360


corresponding Ls are equal
Alternateangles are equal
cointeriorangles are supplementary

is in a Δ addup to 180

Ext L of a Δ sum ofapp int LS
Lsappequal sides in isos Δ are equal

converse sidesappequalLs are equal


Pythag hypotenuse B C



CONGRUENCY E SIMILARITY III

filesin proportion

,Circle geometry lines

line from centre
to chord

line from centre
to midpoint of chord if
Lat centre 2x
catcircle E


is in same segment
i


equal arcs chords
c c
equalangles

L in semicircle

Lat circle 90



tant radius

I
Tangentsfrom same point




Tan chord theorem

converse of tan chord theorem I

,eyelie Quads
180
Opp LS of c q
Opp is
T
converse is in same
segment
Ext L of c q
ExtL toappint l

, Theorems

Linefromcentre to chord
The line drawn from the centre of a circle to a chord bisects the chord




press
vote




converse Line from centre to mid point of chord
The line drawn from the centre of a circle to the midpoint of a chord is perpendicular to the chord