answer:
d: 30
all angles in a triangle have a sum of 180 degrees. Just add 50 and 100 (so 150) and do 180-150=30.
A factor of 20 but not a multiple of 5 would probably be 4
interior angle of a regular 18-gon.
It is easier to calculate the exterior angle of a regular polygon of n-sides (n-gon) by the relation
exterior angle = 360/n
For a 18-gon, n=18, so exterior angle = 360/18=20 °
The value of each interior angle is therefore the supplement, or
Interior angle = 180-20=160 degrees.
Naming of a 9-gon
A polygon with 9 vertices is called a nonagon (in English) or enneagon (French ennéagone, but the English version is sometimes used)
You had a good start with the correct answer.
Exterior angle of a 15-gon
The exterior angle of a 15-gon can be calculated using the relation given in the first paragraph, namely
Exterior angle = 360/15=24 degrees
Answer:
m∠QRS = 52°
Step-by-step explanation:
From the given figure,
In right triangles ΔRQT and ΔRST,
QT = TS = 7.5 units [Given]
RT ≅ RT [Reflexive property]
ΔRQT ≅ ΔRST [By HL theorem of congruence]
Therefore, m(∠QRT) = m(∠SRT) = 26° [CPCTC]
m(∠QRS) = 2m(∠QRT)
= 2×(26°)
= 52°
