Answer:
56844.9 units squared
Step-by-step explanation:
The surface area of a cone is denoted by: , where r is the radius and l is the slant height. The slant height is basically the length from a point on the base circle to the top vertex of the cone.
Here, since our diameter is 50 and diameter is twice the radius, then our radius is r = 50/2 = 25.
To find the slant height, we have to use the Pythagorean Theorem:
, where h is the height
Now, plug these values of r and l into the first equation above:
≈ 56844.9 units squared
I think the answer is 6.32 because it has a desimle point and desimles always have the bigger number like 6.k that means 6 kilometers for short
the key is to write as which can be easily seen as an area of a rectangle with one side length n and the other (n+1). That explains the rectangle made of dots - 3 x 4
Now you only have half of them because of the 1/2. So that explains the lower "triangle" of dots being greyed out - they do not count in the area (upper triangle). So the count of the dark dots corresponds to the original expression.
For n=5 you can draw a similar rectangular matrix with 5 x 6 dots. And count only the upper triangular part.