The projections of the line segment AB¯ on the axes are 5,12,7. Then the length of AB¯ is
2109
21092
1098
None
If d1,d2,d3 are the projections of the line segment of length d on the coordinate axes then d12+d22+d32=d2
It implies that 52+122+72=d225+144+49=d2d=218
Therefore,d=21092