-8
On the number line you either start at -3 or -5 and you got your answer
Answer: The required length of the segment AA' is 11 units.
Step-by-step explanation: Given that the point A(5, 11) is reflected across the X-axis.
We are to find the length of the segment AA'.
We know that
if a point (x, y) is reflected across X-axis, then its co-ordinates becomes (x, -y).
So, after reflection, the co-ordinates of the point A(5, 11) becomes A'(5, -11).
Now, we have the following distance formula :
The DISTANCE between two points P(a, b) and Q(c, d) gives the length of the segment PQ as follows :

Therefore, the length of the segment AA' is given by

Thus, the required length of the segment AA' is 11 units.
Answer:

Step-by-step explanation:
You can multiply on the upper and bottom part by the same number without changing the fraction so 
First of all, expand the left hand side:

Sum like terms:

Add 3 to both sides:

Subtract 3x from both sides:

So this is the solution. Every number smaller than 8 (excluded) is part of the solution of this inequality.