No because a square pyramid must hav a square for its base and a square is not a triangle
answer is not possible
Answer:
c
Step-by-step explanation:
Answer:this item, we are given with the radius equal to 22 cm.
In this measurement of the radius is the hypotenuse of the 30°-60°-90° triangle formed with the half the measurement of the side of the equilateral triangle being opposite to the 60° and equal to the hypotenuse times (1/2)(√3)
Step-by-step explanation:
If we let s be the side of the triangle then,
s/2 = r(1/2)(√3)
Multiplying the equation by 2,
s = r√3
Substituting,
s = (22 cm)(√3) = 22√3
The area of the equilateral triangle is computed through the equation,
A = (√3 / 4)(s²)
Substituting,
A = (√3 / 4)(22√3)² = 628.7 cm²
Therefore, the answer to this item is the first choice.
Answer:
3π square units.
Step-by-step explanation:
We can use the disk method.
Since we are revolving around AB, we have a vertical axis of revolution.
So, our representative rectangle will be horizontal.
R₁ is bounded by y = 9x.
So, x = y/9.
Our radius since our axis is AB will be 1 - x or 1 - y/9.
And we are integrating from y = 0 to y = 9.
By the disk method (for a vertical axis of revolution):
![\displaystyle V=\pi \int_a^b [R(y)]^2\, dy](https://tex.z-dn.net/?f=%5Cdisplaystyle%20V%3D%5Cpi%20%5Cint_a%5Eb%20%5BR%28y%29%5D%5E2%5C%2C%20dy)
So:
Simplify:
Integrate:
![\displaystyle V=\pi\Big[y-\frac{1}{9}y^2+\frac{1}{243}y^3\Big|_0^9\Big]](https://tex.z-dn.net/?f=%5Cdisplaystyle%20V%3D%5Cpi%5CBig%5By-%5Cfrac%7B1%7D%7B9%7Dy%5E2%2B%5Cfrac%7B1%7D%7B243%7Dy%5E3%5CBig%7C_0%5E9%5CBig%5D)
Evaluate (I ignored the 0):
![\displaystyle V=\pi[9-\frac{1}{9}(9)^2+\frac{1}{243}(9^3)]=3\pi](https://tex.z-dn.net/?f=%5Cdisplaystyle%20V%3D%5Cpi%5B9-%5Cfrac%7B1%7D%7B9%7D%289%29%5E2%2B%5Cfrac%7B1%7D%7B243%7D%289%5E3%29%5D%3D3%5Cpi)
The volume of the solid is 3π square units.
Note:
You can do this without calculus. Notice that R₁ revolved around AB is simply a right cone with radius 1 and height 9. Then by the volume for a cone formula:
We acquire the exact same answer.
Answer:
x=21.
Step-by-step explanation:
First you distribute 3 to the parenthesis. You should get 3x-21=42 at this point. Then you add 21 to 42 to get 63. Here you should be at 3x=63. Divide 63 by 3 to get x=3
