Geometry: Midterm formulas etc. Flashcards
(47 cards)
area triangle
1/2bh
area rectangle
bh
area trapezoid
(b1+b2)h/2
area circle
pi(r)squared
area regular polygon
1/2(apothem x side)x(# of triangles)
complementary angles
two angles sum is 90
supplementary angles
two angles sum is 180
sum of interior angles
180(n-2)
sum of exterior angles
360
each interior angle of a regular polygon
180(n-2)/n
each exterior angle of a regular polygon
360/n
distance formula
d=square root of(x1-x2)squared + (y1 - y2)squared
midpoint formula
(x1+x2)/2 , (y1+y2/2)
slope formula
m=(y1-y2)/(x1-x2)
slope intercept form of a line
y=mx+b
point slope formula of a line
y-y1=m(x-x1)
distance from a point to a line
IAx+By+cI / square root of Asquared+Bsquared
pythagorean theorem
a(squared)+b(squared)=c(squared)
trig.
SOHCAHTOA
what does the measure of one exterior angle =
sum of 2 non-adjacent interior angles
what are ways to prove that triangles are congruent
ASA SSS SAS AAS HL
medium
goes from one vertex to the midpoint of the opposite side
altitude
goes from one vertex, perpendicular to the opposite side
perpendicular bisector
perpendicular to a side through the midpoint