Answer:

Step-by-step explanation:
The volume of a pyramid is

where B = area of the base, and h = height of the pyramid
The base is a square.




The side of the base has length 6. Each face of the pyramid is an equilateral triangle with side of length 6.
An altitude of this triangle measures


The pyramid is formed by 4 equilateral triangles whose bases form a square. The tips of the faces meet at a single point on top. The vertical distance from that point to the center of the base is the height of the pyramid.




Volume of the pyramid:



Subtract 1000 by 12. Divide that answer by 2. Add 12 to that answer.
Equations:
1000 -12= 988 988÷2=494 494+12=506
506 boys and 494 girls competed at the special olympics event.
Answer:
c. 12x; 111 cm
Step-by-step explanation:
The regular dodecagon has 12 sides. Each side has a length of x=9.25 cm, and we know that the perimeter of the figure is the sum of the lengths of all the sides: Therefore, since we have 12 sides, the perimeter will be given by the product between the length of each side, x, and the number of sides, 12:

and if we substitute x = 9.25 cm, we find

Answer:
x<-3
Step-by-step explanation:
-2(x+1)+6x<-14
Distribute
-2x-2 + 6x < -14
Combine like terms
4x -2 < -14
Add 2 to each side
4x-2+2 < -14+2
4x < -12
Divide by 4
4x/4 < -12/4
x<-3
the first choice would be the answer