Determining Km and Vmax

I have made a lineweaver-burk graph with some data, but I don't know how to determine Vmax and Km from it? Would you please give me an example of how to do it. Please make a lineweaver-graph with some values and tell me how to determine Km and Vmax. I can figure out the slope from the graph, but cannot figure out Y and x in Y = mx + b. See my graph attached. Here are some random values: 1/Vi (y) 1/[S]i (x)
166.666 .179115
175.000 .537345
233.334 1.07469
315.789 2.68817
456.521 3.58230
611.111 5.37346