Which function has an inverse that is also a function? g(x) = 2x – 3 k(x) = –9x2 f(x) = |x 2| w(x) = –20

Finding the inverse of a function f(x):

1. First, replace f(x) with y. This is done to make the rest of the process easier.

2. Replace every x with a y and replace every y with an x.

3. Solve the equation from Step 2 for y. This is the step where mistakes are most often made so be careful with this step.

4. Replace y with f^{-1}(x). In other words, you’ve managed to find the inverse.

5. Remember: the domain of f is the range of f^{-1} and the range of f is the domain of f^{-1} .

Using this algorithm, you can find the inverse only in case A:

for g(x)=2x-3:

1.

2.

3.

4.

5. The domain and the range of g(x) are all real numbers as well as the domain and the range of

Functions k(x) and f(x) are not one-to-one functions, then you can't find an inverse function. Function w(x) doesn't include x, then you can't also find an inverse function.

correct choice is A.

36 girls

step-by-step explanation:

the 48 boys is 4 parts of the ratio

divide 48 by 4 to obtain one part of the ratio

= 12 ← 1 part of the ratio

3 parts = 3 × 12 = 36 ← number of girls