F(x)=x 2
g(x)=x 2 -8
We can think of g as the translated version of f.

To get the function g, shift f down by 8 units.

Step-by-step explanation:

The constant - 8  at the end of function g(x) suggests the parent function f(x) was translated 8 units down.

Since triangle ABD and triangle BCD are similar traingles, we can establish a proportion between the lengths of corresponding sides:


Notice that we know for our problem that . Also, we can find the length of AD by subtracting CD from AC:




Now we can replace the values in our proportion:


Solving for :





We can conclude that the correct answer is: B. 12