9514 1404 393
Answer:
470.16 cm²
Step-by-step explanation:
The apothem of the base is used for two purposes: to find the area of the base, and to find the slant height of each face.
The apothem of the base for side length s is ...
s/2 = a·tan(π/8)
a = s/(2·tan(π/8)) ≈ 7.24 cm
The slant height of a triangular face is found using the Pythagorean theorem. The apothem of the base and the height are legs of the right triangle whose hypotenuse is the slant height. For slant height x, we have ...
x² = 10² + a² = 100 +52.46
x ≈ √152.46 ≈ 12.35
__
The area of the 8 triangular faces will be ...
A = 1/2Px . . . . where P is the perimeter of the pyramid
The area of the base will be ...
A = 1/2Pa
So, the total surface area is ...
A = 1/2P(a + x) = (1/2)(8)(6 cm)(7.24 +12.35 cm) ≈ 470.16 cm²
Answer:
Step-by-step explanation:
One of the rules of logarithms is ...
log(a^b) = b·log(a)
So ...
Answer:
-3/4
Step-by-step explanation:
Move the 3x over to the side with the 3 so it will become a -3x now you have 4y=-3x+3 now you have to remove the 4 from the y so now you have y=-3/4x+3/4 so you slope will be -3/4
Answer:
12
Step-by-step explanation:
A rhombus is a parallelogram with all four sides equal.
Its diagonals are perpendicular.
Each of the triangles formed by the diagonals and the sides are congruent, so the area of the rhombus is 4 times the area of one of the triangles.
Since the short diagonal is given as 4, each of the triangles can be viewed as having a base of 2. Each triangle's height, h, then is one half the length of the long diagonal.
The are of one of the triangles is 1/2 (base)(height)=(1/2)(2)h
The area of the rhombus is then
4(1/2)(2)h=24
Solving for h gives
h=6
This makes the length of the long diagonal 2h=12
Answer:
a) 
b) 
c) 
Step-by-step explanation:
Assuming the following question: Because of staffing decisions, managers of the Gibson-Marimont Hotel are interested in the variability in the number of rooms occupied per day during a particular season of the year. A sample of 20 days of operation shows a sample mean of 290 rooms occupied per day and a sample standard deviation of 30 rooms
Part a
For this case the best point of estimate for the population variance would be:
Part b
The confidence interval for the population variance is given by the following formula:
The degrees of freedom are given by:
Since the Confidence is 0.90 or 90%, the significance 
and 
, the critical values for this case are:
And replacing into the formula for the interval we got:
Part c
Now we just take square root on both sides of the interval and we got:
