Geometry Problem 973: Three Parallel,
Square, Vertices, Distance Between Two Parallel Lines,
Side, Metric Relations. Level: School, College, Mathematics
Education

Lines L_{1}, L_{2}, and L_{3} are parallel
(Figure below) with line EFG perpendicular to L_{3}.
ABCD is a square with A, B, and D on, L_{3}, L_{1},
and L_{2}, respectively. If EF = 3 and FG =2, find the
side of the square.