Please help, round to the nearest thousandth

Isabel graphed the following system of equations. 2x – y = 6 y = -3x + 4 she came up with the solution (2,-2). what were the 3 steps she did to get that solution? (make sure they are in the correct order)

Graph the equationy= x+3[tex]y = x + 3[/tex]

If the perimeter of the garden is 37 ft. the width is x and the length is 15 ft. what is the width of the garden in feet?