Answer:
Ted
Step-by-step explanation:
Observe the given figure.
Here, angle T and R are the inscribed angles.
And sum of inscribed angles is half of measure of intercepted arcs.
Since, the measure of intercepted arcs is 360 degrees.
Therefore, 

Hence, the sum of the two angles is 180 degrees.
Therefore, these are the supplementary angles.
Therefore, angle T and angle R are supplementary angles.
Hence, proved.
Answer:
17.5
Step-by-step explanation:
Pythagorean Theorem is a^2 + b^2 =c^2
a= 9 , b= 15, c= x
9^2 + 15^2 = c^2
= c^2
c= 17.493 or 17.5 rounded to the nearest tenth
The formula for the lateral surface area of a right circular cone is:

where r is the radius of the base, and l is the slant height.
Plugging in the values we get:
Step-by-step answer:
This is a regular heptagon, means it has 7 <em>congruent</em> sides and 7 <em>congruent </em>vertex angles.
To work with polygons, there is a very important piece of information that you must know to solve the majority of related problems.
This is:
sum of exterior angles of polygons = 360 degrees.
If you don't remember the 360 degrees, think of the sum of exterior angles of an equilateral triangle, which is 3*(180-60)=3*120=360! It works!
For a regular heptagon, c = 360/7=51.43 degrees approx.
This means that each vertex angle measures
vertex angle = 180-c
So since 2d+the vertex angle = 360, we have
2d+(180-c)=360
solve for d:
2d=360-(180-c)=180+c
d=(180+c)/2=90+c/2=115.71 degrees. (approx.)