D a theorem needs to be proven
First you have multiply 6 by both 3x and 8
6*3x = 18x
6*8= 48
18x + 48 + 32 + 12x
now combine like terms
18x + 12x = 30x
48 + 32 = 80
so 30x + 80 is your answer
Answer: -2/3
Step-by-step explanation:
81k^2 - m^2 factors to
(9k + m)(9k - m)
Prove this by FOILing.
First - 81k^2
Outer - (-9km)
Inner - 9km
Last - (-m^2)
Put it into equation form
81k^2 - 9km + 9km - m^2
And combine terms to get the original equation,
81k^2 - m^2.
⭐ Answered by Hyperrspace (Ace) ⭐
⭐ Brainliest would be appreciated, I'm trying to reach genius! ⭐
⭐ If you have questions, leave a comment, I'm happy to help! ⭐
Ok so what we have is a large cylinder with a hollow cylindrical tube running thru the center. The volume of the shaded region should be the volume of the entire large cylinder (C) minus the volume of the small cylindrical tube (c): C - c
The volume of any cylinder is the area of the top circle (pi×r^2) times the height (h) of the cylinder, where r=radius of the circle. So: h×pi×r^2
The heights are the same for C and c, so we can call that h in both, which = 30ft. Now C's radius (R) = 1/2 of diameter, which is 18ft. So R = 9ft
c's radius (r) is 1/2 of its diameter, which is 6ft. So r = 3ft. Now we can set it up:
C - c = (h×pi×R^2) - (h×pi×r^2)
*since the h and pi in both formulae are multiplied by the other variable, we can factor that out:
h×pi(R^2) - h×pi(r^2) = h×pi(R^2-r^2)
h×pi = 30ft.×3.14 = 94.2ft. -->
94.2ft(9ft^2-3ft^2) = 94.2ft(81-9ft^2)
= 94.2ft(72ft^2) = 6782.4 ft.^3
