Square Root Functions

1. Which equation is the inverse of [tex]\( y = 100 - x^2 \)[/tex] ?

A. [tex]\( y = \pm \sqrt{100 - x} \)[/tex]

B. [tex]\( y = 10 \pm \sqrt{x} \)[/tex]

C. [tex]\( y = 100 - \sqrt{x} \)[/tex]

D. [tex]\( y = \pm \sqrt{x - 100} \)[/tex]



Answer :

To find the inverse of the given equation [tex]\( y = 100 - x^2 \)[/tex], follow these steps:

1. Start with the original equation:

[tex]\[ y = 100 - x^2 \][/tex]

2. Swap [tex]\( x \)[/tex] and [tex]\( y \)[/tex] to find the inverse:

[tex]\[ x = 100 - y^2 \][/tex]

3. Solve for [tex]\( y \)[/tex]:

[tex]\[ y^2 = 100 - x \][/tex]

To isolate [tex]\( y \)[/tex], take the square root of both sides:

[tex]\[ y = \pm \sqrt{100 - x} \][/tex]

Therefore, the equation that represents the inverse of [tex]\( y = 100 - x^2 \)[/tex] is:

[tex]\[ y = \pm \sqrt{100 - x} \][/tex]

Now, let's look at the provided answer choices and find the correct one:

1. [tex]\( y = \pm \sqrt{100 - x} \)[/tex]
2. [tex]\( y = 10 \pm \sqrt{x} \)[/tex]
3. [tex]\( y = 100 = \sqrt{x} \)[/tex]
4. [tex]\( y = \pm \sqrt{x - 100} \)[/tex]

The correct answer, based on our step-by-step solution, is:

[tex]\[ y = \pm \sqrt{100 - x} \][/tex]

So the correct choice is the first option:
[tex]\[ y = \pm \sqrt{100 - x} \][/tex]