Graphical Vector Sum in 2-D

Instructions
This simulation provides practice with vector addition. Click the "Reset and Randomize" button to create a random set of three vectors. The magnitude and direction of the vectors are printed to the left of the button. Each vector can be moved by dragging the blue point at its tail.[br][br]Try to calculate the sum of the three vectors and enter your answer in either magnitude and direction or component notation. (The other set of boxes will update as you type.) Check "Plot my answer" to see what your entered vector looks like. Click on "Check my answer" to see if your entered result is within 5% of the accepted value.[br][br]Click the red "Show Solution" button to automatically move the vectors into a head-to-tail configuration and to draw the accepted value. The answer will be shown below the graph.
[list=1][*]Does the starting location of a vector change its value?[/*][*]Click "Show Solution." Notice that the vectors are drawn head-to-tail in the order 1, 2, 3. Does the order actually matter?[/*][*]Click "Reset and Randomize" then calculate the vector sum. Check your answer.[/*][*]Given the sum along with vectors 1 and 2, how could you calculate the value of vector 3?[/*][/list]

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