eCalc - Online Scientific Calculator with integrated Unit Converter. Our free calculator graphs up to 7 implicit equations, finds intersections and lets you save picture of graph to your computer! Also: pan and zoom, table of values. Select " CALCULATOR " in the Navigation Bar (left side of page). 2. Click on Virtual TI 83 Calculator. 3. Select "OK" to move to folder. 4. Open "TI83" folder. 5.