This is what displays in a new "black" window when the graph is clicked on. The image "http://webwork.nwmissouri.edu/webwork2_files/tmp/Precalculus_17-117_Shepherd_Fall_2013//gif/S517944-3523-setHW_1-6prob3image1.png" cannot be displayed because it contains errors.
The "information" on the problem where this occurred is here, from where I reported the "bug", but the error did not occur for the bug fixer.
http://bugs.webwork.maa.org/opt/webwork/courses/Precalculus_17-117_Shepherd_Fall_2013/templates/Library/ASU-topics/setInverseFunctions/faris1.pg_with_problemSeed=3523