Simplifying expressions-Please help!!

The graph shows the distance y, in inches, a pendulum moves to the right (positive displacement) and to the left (negative displacement), for a given number of seconds x. how many seconds are required for the pendulum to move from its resting position and return? enter your answer in the box.

Why is x= 4 a solution to the proportion 14/x 56/1 6

Suppose the equation ||x-a|-b|=2008 has 3 distinct real roots and a not =0. find the value of b.