Using a Polyline feature instead of a Point for Feature layer query multiple sample

[RyanKammerer1]

I'm trying to get the code right for a Polyline feature service of road segments with a related table of inspection history. I've been playing around with the example: Feature layer query multiple | ArcGIS API for JavaScript , but haven't got it to work for a Polyline feature rather than points. I believe the code the is giving me trouble is:

function findWells(evt) {
        grid.setStore(null);
        var selectionQuery = new esri.tasks.Query();
        var tol = map.extent.getWidth()/map.width * 5;
        var x = evt.mapPoint.x;
        var y = evt.mapPoint.y;
        var queryExtent = new esri.geometry.Extent(x-tol,y-tol,x+tol,y+tol,evt.mapPoint.spatialReference);
        selectionQuery.geometry = queryExtent;
        wellFeatureLayer.selectFeatures(selectionQuery,esri.layers.FeatureLayer.SELECTION_NEW);
      }

Any ideas on how to write this function for a polyline?

Thanks!