Answer:
324π in²
Step-by-step explanation:
The surface area of a sphere = 4πr² ( r is the radius )
Calculate r using the volume (V) formula
V = 
πr³
Here V = 972π , thus
πr³ = 972π ( divide both sides by π )
r³ = 972 ( multiply both sides by 3 to clear the fraction )
4r³ = 2916 ( divide both sides by 4 )
r³ = 729 ( take the cube root of both sides )
r = ![\sqrt[3]{729}](https://tex.z-dn.net/?f=%5Csqrt%5B3%5D%7B729%7D)
= 9
Thus
surface area = 4π × 9² = 4π × 81 = 324π in²
The rules are
Let me show you why with a couple of examples: suppose we want to multiply
Since powers are just repeated multiplications, we have
Similarly, we have
This is a perfect square trnomial
(a+b)²=a²+2ab+b²
we see that a=5x and b=2
(5x)²+2(5x)(2)+2²=0
factor
(5x+2)²=0
set equal to zero
5x+2=0
5x=-2
x=-2/5
Step-by-step explanation:
the answer is:
x=180-90-70=20°
800 + 16x = 720 + 21x. Cancel out the 720 to get 80 + 16x = 21x. Subtract 16x from both sides to get 80 = 5x. Divide by 5 to get 16 = x, or x = 16. 16 hours. The charge is 800 + 16(16), = 720 + 21(16) which = 800 + 256 = 720 + 336 which = 1,056 = 1,056. Hope this helped!
