The vertex of ∠𝑨𝑩𝑪 is ●B
symbolic notation:∥
So, a ∥ 𝑏
symbolic notation:⊥
So, c ⊥ 𝑑
Circle
The set of all points equidistant from a point in a plane
congruent
Two figures, segments, triangles, etc. that have the same size, same shape, same measure
∆PQR ≅ ∆LJK
symbolic notation:≅
acute angle
an angle whose measure is less than 90ᴼ
40ᴼ AWWW… Such a CUTE little angle!
symbolic notation:m∠A = 40ᴼ
A
right angle
an angle whose measure is exactly 90ᴼ
symbolic notation:m∠B = 90ᴼ
B
obtuse angle
an angle whose measure is greater than 90ᴼ
symbolic notation:m∠C = 120ᴼ
C120ᴼ
(obtuse angle)
straight angle
an angle whose measure is exactly 180ᴼ
symbolic notation:m∠ABC = 180ᴼ
BA C
HINT: THERE IS ONLY 1 STRAIGHT ANGLE…(thus a straight angle is different from supplementary angles!!!)
two angles whose sum is equal to 90ᴼ
12
m∠1 + m∠2 = 90ᴼ
12
m∠1 + m∠2 = 180ᴼ
two angles whose sum is equal to 180ᴼ
two angles that share a common ray
C
B
AD
Vertical Angles
two angles that are opposite of each other and share a common vertex
A
B
C
D
E
an angle that lies on the exterior of a figure
BA
C