Answer: D
Step-by-step explanation:
If the equation is f(x) = 9x^2 -12, you can solve for the inverse by switching the x and y like this.
x = 9y^2-12.
Then you solve for y.
x = 9y^2-12.
x+12=9y^2
y^2=(x+12)/9
y=sqrt((x+12)/9)
y=sqrt((x+12))/3 which is D
Answer: 6.6 miles
Step-by-step explanation:
Since he finished 22% of his skiing in the morning, that means he still has 78% (100% - 22%) of his skiing left.
The remaining 78% is equivalent to 23.4 miles. We need to know the total miles of the skiing. This will be:
78% of x = 23.4
0.78 × x = 23.4
0.78x = 23.4
x = 23.4 / 0.78
x = 30 miles
Since the total skiing is 30 miles and he has 23.4 miles left, the miles covered in the morning will be:
= 30 - 23.4
= 6.6 miles
Answer:
Option A is the correct answer
Step-by-step explanation:
A. The difference of twice the cube of a number and 11
Answer:
Equation: 
Solve for n: n = 112
Step-by-step explanation:
To first set up the equation, you need to look at the verbal description and translate into numbers and operations:
'three fourths a number' = 
'plus 8' = + 8
'is' =
'20 less' = - 20
'the number' = n
Put the expressions together:
'three fourths a number plus 8': 
'20 less than the number': n - 20
Set them equal to each other and solve:
Add 20 to both sides: 
Subtract 
from both sides: 
Multiply both sides by 
: 
Solve for n: n = 112
About 750 different permutations
