Can someone explain long division to me?

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.

Write 17/20 as a decimal and as a percent.

Complete the solution of the equation. find the value of y when x equals to 1 9x-5y=29