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
Answer:
x ∈ {-4, 2}
Step-by-step explanation:
The x-coefficient (+2) is the sum of the constants in the binomial factors of the equation, and the constant term (-8) is their product.
Since you're familiar with the divisors of 8, you know that the two factors of -8 that total +2 are -2 and +4. These are the constants in the binomial factors:
f(x) = x^2 +2x -8
f(x) = (x -2)(x +4)
The roots of f(x) are the values of x that make these factors be zero. They are x=2 and x=-4.
The roots of f(x) are -4 and 2.
_____
Above is the solution by factoring. We can also "complete the square" to find the roots. Anytime we're looking for roots, we want the values of x that make f(x) = 0.
x^2 +2x -8 = 0
x^2 +2x = 8 . . . . . add the opposite of the constant
x^2 +2x +1 = 8 +1 . . . . . add the square of half the x-coefficient: (2/2)² = 1
(x +1)² = 9 . . . . . . . . . . . write as squares
x +1 = ±√9 = ±3 . . . . . . take the square root
x = -1 ± 3 . . . . . . . . . . . subtract 1
The roots are x=-4, x=2.
Answer:
23
Step-by-step explanation:
Order of Operations: BPEMDAS
1. Brackets
2. Parenthesis
3. Exponents
4. Multiplication
5. Division
6. Addition
7. Subtraction
Left to Right
Step 1: Write expression
7 + (5 - 9)2 + 3(16 - 8)
Step 2: Parenthesis (subtraction)
7 + (-4)2 + 3(8)
Step 3: Parenthesis (multiplication)
7 - 8 + 24
Step 4: Subtract
-1 + 24
Step 5: Add
23
18 cm doing the same thing rn
