3/7 as a percentage (closest as possible)

Find the value of x for which the lines are parallel.

The number if marbles of different colors stored in a hat is listed below: 4 red marbles 10 green marbles 7 blue marbles. without looking in the hat, dan takes out a marble at random. he replaces the marble and then takes out another marble from the hat. what is the probability that dan takes out a blue marble in both draws?

Solve 3x-18=2y and 5x-6y=6 by elimination show work