Answer:
b 19.2
Step-by-step explanation:
a = 
for a circle. We do not want to find the area for a whole circle. We only want to find the area for part of a circle. a hole circle is 360 degrees.
a = 


a = 
(
)
a = 19.2 rounded.
There exists a trigonometric identity which states that,
sin (A - B) = sin A cos B - cos A sin B
This is very similar to the given expression with A equal to 57° and B equal to 13°. The simplified form of the angle is,
sin (57° - 13°) = sin 44°
Answer: x = 27
Step-by-step explanation:
2x+3x+45=180º because all of the angles of a triangle add up to 180
5x=180-45
5x=135
x=135/5
x=27
Answer:

Step-by-step explanation:




Answer:
60°
Step-by-step explanation:
ABCO is a parallelogram (opposite sides are parallel).
AO is equal to the radius of the circle, so BC must also equal the radius.
CO is equal to the radius of the circle, so AB must also equal the radius.
If we draw a line from O to B, we split the parallelogram into two triangles. Since OB is equal to the radius of the circle, each triangle is an equilateral triangle. Therefore, angle A is 60°.