The answer is the last one C
To solve this problem you must apply the proccedure shown below:
1- Solve the substraction in the parenthesis and square it:

2- Apply the distributive property and solve the addition:

The answer is: 
Answer:2<x<6
Step-by-step explanation:
Solve for x
Two the smaller right angled triangles are similar. Therefore:
Answer: a) 4.5