Answer:
Step 2 contains error in the given problem.
Step-by-step explanation:
Given expression is:

Step 1: identifying the LCM.
The LCM identified is 6.
This step is correct.
In the next step, we multiply the LCM with each term of the equation.
Step 2:

However,
In the given solution, the LCM is not multiplied with each term.
Hence,
Step 2 contains error in the given problem.
The inverse of the equation is the square root of x-16. In order to find inverse switch the y and x values and try to isolate y
Answer:
5.66 inches
Step-by-step explanation:

a² + 7² = 9²
a² + 49 = 81
a² + 49 - 49 = 81 - 49
a² = 32
a = square root of 32
a = 5.6568 or 5.66 inches
I used the Pythagorean Theorem to solve this.