Since the angle
100
° is in the second quadrant, the reference angle formula is A
r
=
180
°
−
A
c. A
r
=
180
°
−
100
°
The reference angle is A
r
=
80
°
.
80
°
S = rθ
4.2 = 1*θ
The central angle (θ) is 4.2 radians.
Step-by-step explanation:
Angle A = 4x + 12 = 4(15) + 12 = 72°.
Acute is for angles that are less than 90°.
Obtuse is for angles that are between 90° and 180°, not inclusive.
Right is for angles that are 90°
Hence the answer is acute.
